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A031461

Numbers whose base-4 representation has the same number of 0's as 3's.

1, 2, 5, 6, 9, 10, 12, 19, 21, 22, 25, 26, 28, 35, 37, 38, 41, 42, 44, 49, 50, 52, 56, 71, 75, 77, 78, 83, 85, 86, 89, 90, 92, 99, 101, 102, 105, 106, 108, 113, 114, 116, 120, 135, 139, 141, 142, 147, 149, 150, 153, 154, 156, 163, 165

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OFFSET

1,2

COMMENTS

Union of A031443 and A031448, i.e., numbers k in binary where the difference between numbers of 1's and 0's [A000120(k) - A023416(k) = -A037861(k)] is 1 or 0. - Henry Bottomley, Mar 02 2001

LINKS

Amiram Eldar, Table of n, a(n) for n = 1..10000

MATHEMATICA

Select[Range[165], Equal @@ DigitCount[#, 4, {0, 3}] &] (* Amiram Eldar, Aug 03 2023 *)

Select[Range[200], DigitCount[#, 4, 0]==DigitCount[#, 4, 3]&] (* Harvey P. Dale, Mar 28 2026 *)

CROSSREFS

Cf. A000120, A007090, A023416, A031443, A031448, A037861.

Sequence in context: A286905 A028946 A213713 * A085183 A340289 A133759

Adjacent sequences: A031458 A031459 A031460 * A031462 A031463 A031464

KEYWORD

nonn,base,changed

AUTHOR

Clark Kimberling

STATUS

approved

URL: https://oeis.org/A031461

⇱ A031461 - OEIS