A126210 Number of 8's in decimal expansion of 8^n.

0, 1, 0, 0, 0, 1, 0, 0, 0, 1, 1, 2, 1, 4, 1, 4, 1, 3, 4, 4, 1, 3, 3, 2, 2, 3, 0, 2, 4, 1, 3, 1, 1, 4, 3, 3, 3, 4, 5, 3, 4, 4, 5, 4, 4, 3, 5, 7, 4, 10, 5, 3, 7, 7, 4, 8, 3, 6, 7, 4, 10, 6, 5, 3, 5, 10, 8, 9, 7, 10, 5, 12, 6, 10, 5, 7, 2, 9, 11, 9, 11, 7, 7, 5, 2, 9, 6, 7, 5, 13, 12, 10, 8, 4, 9, 6, 6, 10, 10

Offset: 0

Author

Paolo P. Lava and Giorgio Balzarotti, Dec 20 2006

Keywords

• base
• nonn

Crossrefs

Cf. A065710, A126205, A126206, A126207, A126208, A126209, A126211.

Programs

Maple

P:=proc(n) local i,k,x,y,w,cont; y:=8; k:=y; for i from 0 by 1 to n do x:=y^i; cont:=0; while x>0 do w:=x-trunc(x/10)*10; if w=k then cont:=cont+1; fi; x:=trunc(x/10); od; print(cont); od; end: P(100);

Mathematica

DigitCount[8^Range[0,100],10,8] (* Harvey P. Dale, Jan 28 2013 *)