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A285371 Sum of the entries in the ninth blocks of all set partitions of [n]. 2
9, 460, 13365, 291312, 5313419, 85887795, 1273861815, 17739276489, 235727269842, 3025136223480, 37838768653358, 464684701656546, 5636371498958757, 67862072916294706, 814494099000392487, 9780912755503955712, 117894823818639390505, 1430383074839724093993 (list; graph; refs; listen; history; text; internal format)
OFFSET

9,1

LINKS

Alois P. Heinz, Table of n, a(n) for n = 9..400

Wikipedia, Partition of a set

FORMULA

a(n) = A285362(n,9).

MAPLE

a:= proc(h) option remember; local b; b:=

      proc(n, m) option remember;

        `if`(n=0, [1, 0], add((p-> `if`(j=9, p+ [0,

        (h-n+1)*p[1]], p))(b(n-1, max(m, j))), j=1..m+1))

      end: b(h, 0)[2]

    end:

seq(a(n), n=9..30);

MATHEMATICA

a[h_] := a[h] = Module[{b}, b[n_, m_] := b[n, m] = If[n == 0, {1, 0}, Sum[Function[p, If[j == 9, p + {0, (h - n + 1)*p[[1]]}, p]][b[n - 1, Max[m, j]]], {j, 1, m + 1}]]; b[h, 0][[2]]];

Table[a[n], {n, 9, 30}] (* Jean-Fran├žois Alcover, May 27 2018, from Maple *)

CROSSREFS

Column k=9 of A285362.

Sequence in context: A160478 A020263 A265444 * A061175 A289054 A166879

Adjacent sequences:  A285368 A285369 A285370 * A285372 A285373 A285374

KEYWORD

nonn

AUTHOR

Alois P. Heinz, Apr 17 2017

STATUS

approved

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Last modified September 23 19:18 EDT 2020. Contains 337315 sequences. (Running on oeis4.)