A158095 G.f.: A(x) = exp( Sum_{n>=1} 2*sigma(n,n-1)*x^n/n ).

1, 2, 5, 14, 61, 370, 3454, 40880, 614346, 10848514, 222870183, 5175100204, 134514302384, 3859406052466, 121274242936381, 4139268759072626, 152532132931199062, 6034430112251517608, 255114747410233804986

Offset

0,2

Links

Table of n, a(n) for n=0..18.

Example

G.f.: A(x) = 1 + 2*x + 5*x^2 + 14*x^3 + 61*x^4 + 370*x^5 +...

Prog

(PARI) a(n)=polcoeff(exp(sum(m=1, n, 2*sigma(m, m-1)*x^m/m)+x*O(x^n)), n)

Crossrefs

Cf. A023881, A294645.

Sequence in context: A006847 A008286 A049082 * A227365 A059958 A102019

Adjacent sequences: A158092 A158093 A158094 * A158096 A158097 A158098

Keyword

nonn

Author

Paul D. Hanna, Mar 20 2009

Status

approved