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

1, 28, 463, 5909, 64479, 633796, 5786275, 50033463, 415225854, 3338335646, 26179143977, 201266007483, 1522856635641, 11374331041836, 84061202478127, 615860361908534, 4479596579257904, 32388729758708314, 233011769893620853, 1669336230635613631

Offset: 7

Author

Alois P. Heinz, Oct 21 2018

Keywords

• nonn

Links

• Alois P. Heinz, Table of n, a(n) for n = 7..1187

Crossrefs

Column k=7 of A292746.

Cf. A320737, A320738.

Programs

Maple

b:= proc(n, i, k) option remember; `if`(n=0 or i<2, add(
      Stirling2(n, j), j=0..k), add(b(n-i*j, i-1, k), j=0..n/i))
    end:
a:= n-> (k-> b(n$2, k)-b(n$2, k-1))(7):
seq(a(n), n=7..35);

Formula

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