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A176768 Smallest power of 8 whose decimal expansion contains n. 2
4096, 1, 512, 32768, 64, 512, 64, 32768, 8, 4096, 1073741824, 4398046511104, 512, 134217728, 262144, 2097152, 16777216, 134217728, 1073741824, 68719476736, 2097152, 262144, 2251799813685248, 9223372036854775808, 1073741824 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

COMMENTS

This is to 8 as A176763 is to 3 and as A030001 is to 2.

LINKS

Robert Israel, Table of n, a(n) for n = 0..9999

FORMULA

a(n) = MIN{A001018(i) such that n in decimal representation is a substring of A001018(i)}.

a(n) = 8^A062525(n). - Michel Marcus, Sep 30 2014

EXAMPLE

a(1) = 1 because 8^0 = 1 has "1" as a substring (not a proper substring, though).

a(2) = 512 because 8^3 = 512 has "2" as a substring.

a(3) = 32768 because 8^5 = 32768 has "3" as a substring.

MAPLE

F:= proc(dmax) local R, count, x, N, L, d, i, v;

count:= 0: x:= 1/8: N:= 10^dmax:

while count < N do

  x:= 8*x;

  L:= convert(x, base, 10);

  for d from 1 to min(dmax, nops(L)) do

    for i from 1 to nops(L)-d+1 do

      v:= add(L[j]*10^(j-i), j=i..i+d-1);

      if not assigned(R[v]) then count:= count+1; R[v]:= x fi

od od od:

seq(R[v], v=0..N-1);

end proc:

F(2); # Robert Israel, Dec 25 2019

CROSSREFS

Cf. A001018, A030001, A176763, A176764-A176773.

Sequence in context: A076154 A182685 A182686 * A223601 A186490 A223694

Adjacent sequences:  A176765 A176766 A176767 * A176769 A176770 A176771

KEYWORD

base,easy,nonn

AUTHOR

Jonathan Vos Post, Apr 25 2010

EXTENSIONS

More terms from Sean A. Irvine and Jon E. Schoenfield, May 05 2010

a(0)=4096 inserted by Robert Israel, Dec 25 2019

STATUS

approved

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Last modified September 22 20:23 EDT 2020. Contains 337291 sequences. (Running on oeis4.)