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G.f.: Sum_{k >= 1} x^k/(1-x^k)^(k+1).
15

%I #24 Sep 03 2019 12:06:58

%S 1,3,4,8,6,17,8,24,20,32,12,76,14,51,72,97,18,158,20,213,142,101,24,

%T 491,152,132,248,479,30,915,32,681,398,206,828,1859,38,249,600,2560,

%U 42,2692,44,1686,2864,347,48,6166,1766,3405,1192,2811,54,6796,4424,9987

%N G.f.: Sum_{k >= 1} x^k/(1-x^k)^(k+1).

%H Seiichi Manyama, <a href="/A081543/b081543.txt">Table of n, a(n) for n = 1..10000</a> (terms 1..999 from Harvey P. Dale)

%F If p is prime then a(p)=p+1.

%F a(n) = Sum_{d|n} binomial(d-1+n/d,d). - _R. J. Mathar_, Feb 21 2009

%t With[{nn=50},CoefficientList[Series[Sum[x^k/(1-x^k)^(k+1),{k,nn}],{x,0,nn}],x]] (* _Harvey P. Dale_, May 28 2017 *)

%o (PARI) a(n)=if(n<1,0,polcoeff(sum(k=1,n,1/(1-x^k)^k,x*O(x^(n^2))),n))

%Y Cf. A157019.

%K nonn

%O 1,2

%A _Benoit Cloitre_, Apr 21 2003

%E Description corrected by _Vladeta Jovovic_, Aug 22 2003

%E Corrected offset _R. J. Mathar_, Feb 21 2009