A035062 Numbers n such that 2^n does not contain the digit 7.
0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 16, 18, 19, 22, 23, 25, 28, 33, 41, 42, 49, 50, 54, 61, 71
Offset: 1
Crossrefs
Cf. similar sequences listed in A035064.
Programs
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Magma
[n: n in [0..1000] | not 7 in Intseq(2^n) ]; // Vincenzo Librandi, May 06 2015
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Mathematica
Join[{0}, Select[ Range@10000, FreeQ[ IntegerDigits[2^# ], 7] &]] (* Shyam Sunder Gupta, Sep 01 2007 *) -
PARI
is(n)=!#select(k->k==7, Set(digits(2^n))) \\ Charles R Greathouse IV, May 06 2015
Extensions
Edited by N. J. A. Sloane, May 21 2008 at the suggestion of R. J. Mathar
Initial 0 added and Mathematica code adapted by Vincenzo Librandi, May 06 2015
Comments