OFFSET
0,3
EXAMPLE
a(3) = 3^3 + 4^4 + 5^5 = 3408.
MATHEMATICA
Table[Sum[k^k, {k, n, 2 n - 1}], {n, 0, 13}] (* Michael De Vlieger, Oct 05 2015 *)
PROG
(PARI) vector(20, n, n--; sum(k=n, 2*n-1, k^k))
(Sage) [sum(k^k for k in (n..2*n-1)) for n in (0..20)] # Bruno Berselli, Oct 05 2015
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Colin Barker, Oct 04 2015
STATUS
approved