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A320820 Number of partitions of n with exactly seven sorts of part 1 which are introduced in ascending order. 2

%I #4 Oct 21 2018 12:34:29

%S 1,28,463,5909,64479,633796,5786275,50033463,415225854,3338335646,

%T 26179143977,201266007483,1522856635641,11374331041836,84061202478127,

%U 615860361908534,4479596579257904,32388729758708314,233011769893620853,1669336230635613631

%N Number of partitions of n with exactly seven sorts of part 1 which are introduced in ascending order.

%H Alois P. Heinz, <a href="/A320820/b320820.txt">Table of n, a(n) for n = 7..1187</a>

%F a(n) = A320738(n) - A320737(n).

%p b:= proc(n, i, k) option remember; `if`(n=0 or i<2, add(

%p Stirling2(n, j), j=0..k), add(b(n-i*j, i-1, k), j=0..n/i))

%p end:

%p a:= n-> (k-> b(n$2, k)-b(n$2, k-1))(7):

%p seq(a(n), n=7..35);

%Y Column k=7 of A292746.

%Y Cf. A320737, A320738.

%K nonn

%O 7,2

%A _Alois P. Heinz_, Oct 21 2018

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Last modified April 24 10:11 EDT 2024. Contains 371935 sequences. (Running on oeis4.)