|
%I #19 May 01 2021 17:43:12
%S 1,-1,-3,-2,1,9,11,15,6,-18,-46,-54,-115,-101,32,82,182,455,804,915,
%T 434,-114,196,-974,-3507,-6913,-7555,-5081,-4480,-7463,-4861,7677,
%U 25779,56080,76015,51021,53996,104670,114132,93920,-33843,-233380,-491936,-658774,-597698,-601576
%N Expansion of Product_{k>=1} (1 - x^k * (k + x)).
%H Seiichi Manyama, <a href="/A336977/b336977.txt">Table of n, a(n) for n = 0..1000</a>
%F G.f.: exp( - Sum_{k>=1} x^k * Sum_{d|k} (k/d + x)^d / d).
%t m = 45; CoefficientList[Series[Product[1 - x^k*(k + x), {k, 1, m}], {x, 0, m}], x] (* _Amiram Eldar_, May 01 2021 *)
%o (PARI) N=66; x='x+O('x^N); Vec(prod(k=1, N, 1-x^k*(k+x)))
%o (PARI) N=66; x='x+O('x^N); Vec(exp(-sum(k=1, N, x^k*sumdiv(k, d, (k/d+x)^d/d))))
%Y Convolution inverse of A336975.
%Y Cf. A022661, A306565, A336976, A336978, A336979, A336980.
%K sign
%O 0,3
%A _Seiichi Manyama_, Aug 09 2020
|
