A039370 Numbers whose base-9 representation has the same nonzero number of 1's and 7's.

16, 64, 88, 106, 115, 124, 133, 142, 144, 146, 147, 148, 149, 150, 152, 160, 178, 226, 259, 307, 340, 388, 421, 469, 502, 550, 568, 576, 578, 579, 580, 581, 582, 584, 586, 595, 604, 613, 622, 640, 664, 712, 736, 754, 763, 772, 781, 790, 792, 794, 795, 796, 797

Offset

1,1

Links

Chris R. Rehmann, Table of n, a(n) for n = 1..10000

Mathematica

Select[Range[800], DigitCount[#, 9, 1]==DigitCount[#, 9, 7]>0&] (* Harvey P. Dale, Jan 30 2021 *)

Prog

(MATLAB) x = 0:797; d = dec2base(x, 9)-'0'; s1 = sum(d==1, 2); s2 = sum(d==7, 2); a = x(s1==s2 & s1>0); disp(regexprep(num2str(a), ' +', ', ')) % Chris R. Rehmann, Apr 06 2026

Crossrefs

Cf. A007095, A039089.

Cf. A039365, A039366, A039367, A039368, A039369, A039371.

Cf. A039363, A039376, A039381, A039385, A039388, A039390.

Sequence in context: A340588 A352475 A305242 * A324880 A304476 A129588

Adjacent sequences: A039367 A039368 A039369 * A039371 A039372 A039373

Keyword

nonn,base,easy

Author

Olivier Gérard

Status

approved