A039255 Numbers whose base-12 representation has the same number of 5's and 7's.

0, 1, 2, 3, 4, 6, 8, 9, 10, 11, 12, 13, 14, 15, 16, 18, 20, 21, 22, 23, 24, 25, 26, 27, 28, 30, 32, 33, 34, 35, 36, 37, 38, 39, 40, 42, 44, 45, 46, 47, 48, 49, 50, 51, 52, 54, 56, 57, 58, 59, 67, 72, 73, 74, 75, 76, 78, 80, 81, 82, 83, 89, 96, 97, 98, 99, 100

Offset

1,3

Links

Vincenzo Librandi, Table of n, a(n) for n = 1..1000

Mathematica

Select[Range[0, 200], DigitCount[#, 12, 5]==DigitCount[#, 12, 7]&] (* Harvey P. Dale, Jun 23 2011 *)

Prog

(PARI) base(n, b=16, s=0) = { local( a=[ n%b ]); while( 0<n\=b, a=concat( n%b, a )); if( s, s=32*s+23; Strchr( vectorsmall( #a, i, if(a[i]>9, s, 48)+a[i] )), a) }
list_A039255(MAX)=my(c=0); for(n=0, MAX, sum(k=1, #b=base(n, 12), (b[k]==5)-(b[k]==7)) & next; c++ & print1(n", ")) \\ M. F. Hasler, Sep 11 2009
(Magma) [n: n in [0..100] | Multiplicity(S, 5) eq Multiplicity(S, 7) where S is {*d: d in Intseq(n, 12)*}]; // Bruno Berselli, Oct 20 2012

Crossrefs

Sequence in context: A231236 A346131 A151988 * A039196 A039147 A039107

Adjacent sequences: A039252 A039253 A039254 * A039256 A039257 A039258

Keyword

nonn,base,easy

Author

Olivier Gérard

Extensions

An incorrect g.f. was deleted by N. J. A. Sloane, Sep 13 2009 (cf. A151988).

Status

approved