A055223 One-fourth the digital sum of base 5 representations of 2^n.

1, 1, 1, 1, 2, 1, 1, 2, 3, 3, 3, 3, 2, 3, 4, 5, 5, 5, 4, 3, 5, 6, 7, 5, 8, 8, 6, 8, 10, 10, 8, 6, 7, 8, 8, 10, 7, 9, 9, 10, 11, 10, 9, 10, 9, 11, 11, 11, 11, 12, 13, 13, 12, 14, 10, 14, 17, 15, 13, 13, 12, 15, 14, 16, 15, 12, 14, 15, 15, 16, 15, 15, 15, 16, 13, 12, 16, 17, 14, 20, 20, 20

Offset

2,5

Links

Table of n, a(n) for n=2..83.

Example

a(19) = 4 because 2^20 = 1048576 = 232023301 (to scale 5) and (2+3+2+0+2+3+3+0+1)/4 = 4

Mathematica

a[n_] := 1/4* Module[{aux = IntegerDigits[2^(n + 1), 5]}, Sum[aux[[i]], {i, 1, Length[aux]}]] [From José María Grau Ribas, Feb 13 2010]

Crossrefs

Cf. A000866.

Sequence in context: A054989 A051631 A073725 * A174807 A181572 A287731

Adjacent sequences: A055220 A055221 A055222 * A055224 A055225 A055226

Keyword

nonn,base

Author

Lekraj Beedassy, Jun 20 2000

Extensions

More terms from James A. Sellers, Jul 04 2000

Status

approved