A039369 Numbers whose base-9 representation has the same nonzero number of 1's and 6's.

15, 55, 87, 105, 114, 123, 132, 135, 137, 138, 139, 140, 142, 143, 150, 159, 177, 217, 258, 298, 339, 379, 420, 460, 487, 495, 497, 498, 499, 500, 502, 503, 505, 514, 523, 532, 550, 559, 582, 622, 663, 703, 735, 753, 762, 771, 780, 783, 785, 786, 787, 788, 790

Offset

1,1

Links

Robert Israel, Table of n, a(n) for n = 1..10000

Maple

filter:= proc(n) local L, a1;
  L:= convert(n, base, 9);
  a1:= numboccur(1, L);
  a1 > 0 and numboccur(6, L)=a1
end proc:
select(filter, [$1..1000]); # Robert Israel, Sep 27 2018

Mathematica

Select[Range[1000], DigitCount[#, 9, 1]==DigitCount[#, 9, 6]>0&] (* Harvey P. Dale, Oct 15 2014 *)

Prog

(MATLAB) x = 0:790; d = dec2base(x, 9)-'0'; s1 = sum(d==1, 2); s2 = sum(d==6, 2); a = x(s1==s2 & s1>0); disp(regexprep(num2str(a), ' +', ', ')) % Chris R. Rehmann, Apr 05 2026

Crossrefs

Cf. A007095, A039088.

Cf. A039365, A039366, A039367, A039368, A039370, A039371.

Cf. A039362, A039375, A039380, A039384, A039387.

Sequence in context: A379122 A225509 A235533 * A119138 A043192 A043972

Adjacent sequences: A039366 A039367 A039368 * A039370 A039371 A039372

Keyword

nonn,base,easy

Author

Olivier Gérard

Status

approved