|
|
A308037
|
|
a(n) = Sum_{d|n} Stirling2(n,d).
|
|
9
|
|
|
1, 2, 2, 9, 2, 123, 2, 1830, 3027, 43038, 2, 2023728, 2, 49337473, 213142023, 2313595723, 2, 216927216877, 2, 6712023695345, 82312699558575, 366282502967439, 2, 113350450913387211, 2436684974110753, 1850568574287104493, 106563274551407600878, 231678790379913209098, 2
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
1,2
|
|
LINKS
|
|
|
FORMULA
|
|
|
MAPLE
|
a:= n-> add(Stirling2(n, d), d=numtheory[divisors](n)):
|
|
MATHEMATICA
|
a[n_] := a[n] = Sum[StirlingS2[n, d], {d, Divisors[n]}]; Table[a[n], {n, 1, 29}]
|
|
PROG
|
(PARI) a(n) = sumdiv(n, d, stirling(n, d, 2)); \\ Michel Marcus, May 10 2019
|
|
CROSSREFS
|
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|