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

Offset: 0

Author

Jeff Burch

Keywords

• nonn
• base

Links

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

Crossrefs

Cf. A045512 (excludes zero digits).

Programs

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 *)

PARI

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

PARI

apply( {A045503(n)=vecsum([d^d|d<-digits(n+!n)])}, [0..44]) \\ M. F. Hasler, Oct 01 2024

Extensions

Checked by Neven Juric (neven.juric(AT)apis-it.hr), Feb 04 2008