OFFSET
0,2
COMMENTS
The usual convention in the OEIS is that 0^0 = 1. This sequence could therefore be defined as Sum_{j=0..n} j^j. See also A001923.
LINKS
T. D. Noe, Table of n, a(n) for n = 0..100
FORMULA
a(n) ~ n^n. - Vaclav Kotesovec, Nov 27 2017
EXAMPLE
a(4) = 1 + 1^1 + 2^2 + 3^3 + 4^4 = 1 + 1 + 4 + 27 + 256 = 289.
MATHEMATICA
Table[Sum[Sum[Binomial[n, k] StirlingS2[n, k] k!, {k, 0, n}], {n, 0, m}], {m, 0, 20}] (* Geoffrey Critzer, Mar 18 2009 *)
Join[{1}, Accumulate[Table[n^n, {n, 20}]]+1] (* Harvey P. Dale, Aug 31 2016 *)
PROG
(PARI) { a=0; for (n=0, 100, write("b062970.txt", n, " ", a+=n^n) ) } \\ Harry J. Smith, Aug 14 2009
(Python)
from itertools import count, accumulate, islice
def A062970_gen(): # generator of terms
yield from accumulate((k**k for k in count(1)), initial=1)
CROSSREFS
KEYWORD
nonn
AUTHOR
Henry Bottomley, Jul 23 2001
STATUS
approved