A039407 - OEIS

A039407

Numbers whose base-10 representation has the same nonzero number of 1's and 7's.

17, 71, 107, 127, 137, 147, 157, 167, 170, 172, 173, 174, 175, 176, 178, 179, 187, 197, 217, 271, 317, 371, 417, 471, 517, 571, 617, 671, 701, 710, 712, 713, 714, 715, 716, 718, 719, 721, 731, 741, 751, 761, 781, 791, 817, 871, 917, 971, 1007, 1027

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OFFSET

1,1

LINKS

Table of n, a(n) for n=1..50.

MATHEMATICA

Select[Range[1200], DigitCount[#, 10, 1]==DigitCount[#, 10, 7]>0&] (* Harvey P. Dale, Jun 10 2023 *)

CROSSREFS

Sequence in context: A179038 A179039 A152295 * A043230 A044010 A106921

Adjacent sequences: A039404 A039405 A039406 * A039408 A039409 A039410

KEYWORD

nonn,base,easy

AUTHOR

Olivier Gérard

STATUS

approved