A351897 Numbers that in factorial-base representation have digits with an alternating parity.

0, 1, 2, 5, 7, 11, 14, 19, 23, 26, 38, 55, 59, 67, 71, 74, 86, 103, 107, 115, 119, 127, 131, 139, 143, 175, 179, 187, 191, 223, 227, 235, 239, 266, 278, 314, 326, 367, 371, 379, 383, 415, 419, 427, 431, 463, 467, 475, 479, 506, 518, 554, 566, 607, 611, 619, 623

Offset

1,3

Links

Amiram Eldar, Table of n, a(n) for n = 1..20477 (terms below 10!)

Example

7 is a term since its factorial-base representation is 101 and the parities of its digits are odd, even, odd.

Mathematica

max = 7; q[n_] := AllTrue[Differences@ Mod[IntegerDigits[n, MixedRadix[Range[max, 2, -1]]], 2], # != 0 &]; Select[Range[0, 1000], q]

Crossrefs

Cf. A007623.

Similar sequences: A000975 (binary), A030141 (decimal), A033068 (ternary), A179970 (quaternary).

Subsequences: A033312, A138524, A341900.

Sequence in context: A099835 A133436 A363244 * A184676 A191175 A191125

Adjacent sequences: A351894 A351895 A351896 * A351898 A351899 A351900

Keyword

nonn,base

Author

Amiram Eldar, Feb 24 2022

Status

approved