OFFSET
0,6
LINKS
Alois P. Heinz, Table of n, a(n) for n = 0..698
C. G. Bower, Transforms (2)
FORMULA
"EGJ" (unordered, element, labeled) transform of 0, 1, 1, 1...
E.g.f: Product_{k >= 2} (1 + x^k/k!). - Andrew Howroyd, Sep 11 2018
MAPLE
b:= proc(n, i) option remember;
`if`(n=0, 1, `if`(i<2, 0, b(n, i-1)+
`if`(i>n, 0, b(n-i, i-1)*binomial(n, i))))
end:
a:= n-> b(n$2):
seq(a(n), n=0..30); # Alois P. Heinz, May 11 2016
MATHEMATICA
b[n_, i_] := b[n, i] = If[n == 0, 1, If[i < 2, 0, b[n, i - 1] + If[i > n, 0, b[n - i, i - 1]*Binomial[n, i]]]]; a[n_] := b[n, n]; Table[a[n], {n, 0, 30}] (* Jean-François Alcover, Feb 27 2017, after Alois P. Heinz *)
PROG
(PARI) seq(n)={Vec(serlaplace(prod(k=2, n, 1 + x^k/k! + O(x*x^n))))} \\ Andrew Howroyd, Sep 11 2018
CROSSREFS
KEYWORD
nonn
AUTHOR
EXTENSIONS
a(0)=1 prepended by Alois P. Heinz, May 11 2016
STATUS
approved