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A057159 Numbers n such that n divides s(n-1), where s(1) = 1, s(n) = s(n-1) + (n+1)*3^n. 1
4, 13, 35, 52, 95, 119, 169, 676, 11596, 57577, 159484, 276773 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

No other terms below 300000. - Vaclav Kotesovec, May 05 2018

s(n) = 1, 28, 136, 541, 1999, 7102, 24598,... 4*s(n) = 3^(n+1)*(2n+1)-23, with g.f. x*(-1-21*x+45*x^2) / ( (x-1)*(-1+3*x)^2 ). - R. J. Mathar, May 05 2018

LINKS

Table of n, a(n) for n=1..12.

MATHEMATICA

seq = RecurrenceTable[{s[n] == s[n - 1] + (n + 1)*3^n, s[1] == 1}, s, {n, 1, 20000}]; Select[Range[1, Length[seq]], Divisible[seq[[# - 1]], #] &] (* Vaclav Kotesovec, May 05 2018 *)

CROSSREFS

Sequence in context: A127981 A296303 A089453 * A189588 A266357 A095941

Adjacent sequences:  A057156 A057157 A057158 * A057160 A057161 A057162

KEYWORD

nonn,more

AUTHOR

Robert G. Wilson v, Sep 13 2000

EXTENSIONS

Minor edits by Altug Alkan, May 05 2018

a(10)-a(12) from Vaclav Kotesovec, May 05 2018

STATUS

approved

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Last modified December 6 04:14 EST 2019. Contains 329784 sequences. (Running on oeis4.)