A045503 - OEIS

A045503

If decimal expansion of n is ab...d, a(n) = a^a + b^b +...+ d^d.

1, 1, 4, 27, 256, 3125, 46656, 823543, 16777216, 387420489, 2, 2, 5, 28, 257, 3126, 46657, 823544, 16777217, 387420490, 5, 5, 8, 31, 260, 3129, 46660, 823547, 16777220, 387420493, 28, 28, 31, 54, 283, 3152, 46683, 823570, 16777243, 387420516, 257, 257, 260

(list; graph; refs; listen; history; text; internal format)

OFFSET

0,3

LINKS

Harvey P. Dale, Table of n, a(n) for n = 0..1000

MAPLE

a:= n-> add(i^i, i=convert(n, base, 10)):

seq(a(n), n=0..42); # Alois P. Heinz, Apr 29 2022

MATHEMATICA

f[n_]:=Module[{idn=IntegerDigits[n]/.{0->1}}, Total[idn^idn]]; Array[f, 100, 0] (* Harvey P. Dale, May 14 2012 *)

PROG

(PARI) a(n)=if(n, n=digits(n); sum(i=1, #n, n[i]^n[i]), 1) \\ Charles R Greathouse IV, Oct 07 2015