Aperiodic Monotonic Divergent Series of Integers

SPECIES

Monotonic divergent series of natural numbers (starting from 1)

\displaystyle \sum_{n\geq1} n = 1+2+3+4+5+6+\cdots = G_2 = -\dfrac{1}{12}   (unstable)

Monotonic divergent series of odd numbers (starting from 1)

\displaystyle \sum_{n\geq1} (2n-1) = 1+3+5+7+9+11+\cdots = \dfrac{1}{3}   (unstable)

Monotonic divergent series of Hilbert numbers (starting from 1)

\displaystyle \sum_{n\geq1} (4n-3) = 1+5+9+13+17+21+\cdots = \dfrac{7}{6}   (unstable)

Monotonic divergent series of square numbers (starting from 1)

\displaystyle \sum_{n\geq1} n^2 = 1+4+9+16+25+36+\cdots = 0   (unstable)

Monotonic divergent series of cubic numbers (starting from 1)

\displaystyle \sum_{n\geq1} n^3 = 1+8+27+64+125+216+\cdots = \dfrac{1}{120}   (unstable)

Monotonic divergent series of quartic numbers (starting from 1)

\displaystyle \sum_{n\geq1} n^4 = 1+16+81+256+625+1296+\cdots = 0   (unstable)

Monotonic divergent series of quintic numbers (starting from 1)

\displaystyle \sum_{n\geq1} n^5 = 1+32+243+1024+3125+\cdots = -\dfrac{1}{252}   (unstable)

Monotonic divergent series of triangular numbers (starting from 1)

\displaystyle \sum_{n\geq1} \dfrac{n(n+1)}{2} = 1+3+6+10+15+21+\cdots = -G_3 = -\dfrac{1}{24}   (unstable)

Monotonic divergent series of tetrahedral numbers (starting from 1)

\displaystyle \sum_{n\geq1} \dfrac{n(n+1)(n+2)}{6} = 1+4+10+20+35+56+\cdots = G_4 = -\dfrac{19}{720}   (unstable)

Monotonic divergent series of pentachoric numbers (starting from 1)

\displaystyle \sum_{n\geq1} \dfrac{n(n+1)(n+2)(n+3)}{24} = 1+5+15+35+70+126+\cdots = -G_5 = -\dfrac{3}{160}   (unstable)

Monotonic divergent series of pentagonal numbers (starting from 1)

\displaystyle \sum_{n\geq1} \dfrac{n(3n-1)}{2} = 1+5+12+22+35+51+\cdots = \dfrac{1}{24}   (unstable)

Monotonic divergent series of hexagonal numbers (starting from 1)

\displaystyle \sum_{n\geq1} n(2n-1) = 1+6+15+28+45+66+\cdots = \dfrac{1}{12}   (unstable)

Monotonic divergent series of centered square numbers (starting from 1)

\displaystyle \sum_{n\geq1} (2n^2-2n+1) = 1+5+13+25+41+61+\cdots = -\dfrac{1}{3}   (unstable)

Monotonic divergent series of square-triangular numbers (starting from 1)

\displaystyle \sum_{n\geq1} \dfrac{(17+12\sqrt{2})^n + (17-12\sqrt{2})^n - 2}{32}

= 1+36+1225+41616+1413721+48024900+\cdots = 0   (unstable)

Monotonic divergent series of powers of 2 (starting from 1)

\displaystyle \sum_{n\geq0} 2^n = 1+2+4+8+16+32+\cdots = -1   (stable)

Monotonic divergent series of powers of 3 (starting from 1)

\displaystyle \sum_{n\geq0} 3^n = 1+3+9+27+81+243+\cdots = -\dfrac{1}{2}   (stable)

Monotonic divergent series of powers of 4 (starting from 1)

\displaystyle \sum_{n\geq0} 4^n = 1+4+16+64+256+1024+\cdots = -\dfrac{1}{3}   (stable)

Monotonic divergent series of powers of 5 (starting from 1)

\displaystyle \sum_{n\geq0} 5^n = 1+5+25+125+625+3125+\cdots = -\dfrac{1}{4}   (stable)

Monotonic divergent series of Mersenne numbers (starting from 1)

\displaystyle \sum_{n\geq0} (2^n-1) = 1+3+7+15+31+63+\cdots = -\dfrac{3}{2}   (unstable)

Monotonic divergent series of natural numbers times powers of 2 (starting from 1)

\displaystyle \sum_{n\geq1} n2^{n-1} = 1+4+12+32+80+192+\cdots = 1   (stable)

Monotonic divergent series of factorial numbers (starting from 0 or 1)

\displaystyle \sum_{n\geq0} n! = 1+1+2+6+24+120+\cdots = \dfrac{\text{Ei}(1)}{e} = \dfrac{\text{li}(e)}{e} \quad \textit{(stable)} \\ \approx 0.697174883235066068765478681919551595317175430954369517320054807\ldots

\displaystyle \sum_{n\geq1} n! = 1+2+6+24+120+\cdots = \dfrac{\text{Ei}(1)}{e} \,-\,1 = \dfrac{\text{li}(e)}{e} \,-\, 1 \quad \textit{(stable)} \\ \approx -0.30282511676493393123452131808044840468282456904563048267994519\ldots

Monotonic divergent series of Fibonacci numbers (starting from 1+1)

\displaystyle \sum_{n\geq1} F_n = 1+1+2+3+5+8+13+21+\cdots = -1   (stable)

Monotonic divergent series of squared Fibonacci numbers (starting from 1+1)

\displaystyle \sum_{n\geq1} F_n^2 = 1+1+4+9+25+64+169+441+\cdots = 0   (stable)

Erratum: above sum corrected by Denis Rogov on 04 May 2023

Monotonic divergent series of Lucas numbers (starting from 1+3)

\displaystyle \sum_{n\geq1} L_n = 1+3+4+7+11+18+29+47+\cdots = -3   (stable)

Monotonic divergent series of squared Lucas numbers (starting from 1+9)

\displaystyle \sum_{n\geq1} L_n^2 = 1+9+16+49+121+324+841+\cdots = -2   (stable)

Erratum: above sum corrected by Denis Rogov on 25 Sep 2023

Monotonic divergent series of Padovan numbers (starting from 1+0+1)

\displaystyle \sum_{n\geq1} P_n = 1+0+1+1+1+2+2+3+4+\cdots = -1   (stable)

Monotonic divergent series of Pell numbers (starting from 1+2)

\displaystyle \sum_{n\geq1} P_n = 1+2+5+12+29+70+169+\cdots = -\dfrac{1}{2}   (stable)

Monotonic divergent series of Catalan numbers (starting from 1)

\displaystyle \sum_{n\geq1} C_n = 1+2+5+14+42+132+\cdots = -\dfrac{1}{2}   (stable)

Monotonic divergent series of Jacobsthal numbers (starting from 1)

\displaystyle \sum_{n\geq1} J_n = 1+1+3+5+11+21+43+85+\cdots = -\dfrac{1}{2}   (stable)

Monotonic divergent series of Perrin numbers (starting from 3+0)

\displaystyle \sum_{n\geq1} P_n = 3+0+2+3+2+5+5+7+10+\cdots = -2   (stable)

Monotonic divergent series of Leonardo numbers (starting from 1+1)

\displaystyle \sum_{n\geq1} L_n = 1+1+3+5+9+15+25+41+\cdots =  -\dfrac{3}{2}   (unstable)

Monotonic divergent series of polite numbers (starting from 1+3)

\displaystyle \sum_{n\geq1} P_n = 1+3+5+6+7+9+10+11+\cdots = \dfrac{25}{12}   (unstable)

Monotonic divergent series of Collatz numbers

\displaystyle \sum_{n\geq1} \begin{cases} 3n+1 \quad \text{if n is odd} \\ n/2 \qquad \text{ if n is even} \end{cases}

= 4+1+10+2+16+3+22+\cdots = \dfrac{1}{6}   (unstable)