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Number of partitions of n such that 5*(least part) + 1 = greatest part.
2

%I #11 May 17 2023 08:34:57

%S 0,0,0,0,0,0,1,1,2,3,5,7,12,14,21,27,37,46,63,75,97,119,149,178,222,

%T 260,317,373,447,520,620,713,839,965,1123,1282,1488,1687,1939,2196,

%U 2508,2826,3220,3610,4087,4578,5157,5755,6472,7199,8060,8953,9991,11069,12330,13625,15134,16708,18508

%N Number of partitions of n such that 5*(least part) + 1 = greatest part.

%F G.f.: Sum_{k>=1} x^(6*k+1)/Product_{j=k..5*k+1} (1-x^j).

%o (PARI) my(N=60, x='x+O('x^N)); concat([0, 0, 0, 0, 0, 0], Vec(sum(k=1, N, x^(6*k+1)/prod(j=k, 5*k+1, 1-x^j))))

%Y Cf. A049820, A237828, A363075, A363076.

%Y Cf. A237827.

%K nonn

%O 1,9

%A _Seiichi Manyama_, May 17 2023