A204819 Final nonzero digit of n^n in base 9.

1, 1, 4, 3, 4, 2, 1, 7, 1, 1, 1, 5, 1, 4, 7, 6, 7, 8, 1, 1, 4, 3, 4, 2, 1, 7, 1, 3, 1, 5, 1, 4, 7, 6, 7, 8, 1, 1, 4, 3, 4, 2, 1, 7, 1, 8, 1, 5, 1, 4, 7, 6, 7, 8, 1, 1, 4, 3, 4, 2, 1, 7, 1, 1, 1, 5, 1, 4, 7, 6, 7, 8, 1, 1, 4, 3, 4, 2, 1, 7, 1, 1, 1, 5, 1

Offset: 0

Author

José María Grau Ribas, Jan 19 2012

Keywords

• nonn
• base

Links

• Harvey P. Dale, Table of n, a(n) for n = 0..1000
• José María Grau and Antonio M. Oller-Marcén, On the last digit and the last non-zero digit of n^n in base b, arXiv preprint arXiv:1203.4066 [math.NT], 2012.

Programs

Mathematica

f[0]=1;f[n_]:=Module[{m=n^n},While[Mod[m,9]==0,m=m/9];Mod[m,9]];y=Table[f[i],{i,0,100}]
Join[{1},Mod[#/10^IntegerExponent[#],10]&/@Table[FromDigits[ IntegerDigits[ n^n,9]],{n,100}]] (* Harvey P. Dale, Jan 30 2021 *)