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A113023 Number of terms in A095810 which have n digits. 2
5, 18, 90, 450, 2250, 11250, 56250, 281250, 1406250, 7031250 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

a(n+1)/a(n) = ~5.

LINKS

Table of n, a(n) for n=1..10.

FORMULA

t = sorted union of 2^k (mod 10^n), 0<k<=5^n; then count only those which have n digits.

MATHEMATICA

Do[t = Union[ Table[ PowerMod[2, i, 10^n], {i, 5^n}]]; Print[ Length[ Select[t, Floor[ Log[10, # ] + 1] == n &]]], {n, 10}] (* Robert G. Wilson v, Aug 27 2004 *)

CROSSREFS

Cf. A095810, A113022.

Sequence in context: A185652 A009305 A097574 * A174082 A188329 A165962

Adjacent sequences:  A113020 A113021 A113022 * A113024 A113025 A113026

KEYWORD

nonn,base

AUTHOR

Paul D. Hanna and Robert G. Wilson v, Aug 27 2004

STATUS

approved

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Last modified September 21 15:26 EDT 2017. Contains 292300 sequences.