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A351893
Numbers that contain only even digits in their factorial-base representation.
5
0, 4, 12, 16, 48, 52, 60, 64, 96, 100, 108, 112, 240, 244, 252, 256, 288, 292, 300, 304, 336, 340, 348, 352, 480, 484, 492, 496, 528, 532, 540, 544, 576, 580, 588, 592, 1440, 1444, 1452, 1456, 1488, 1492, 1500, 1504, 1536, 1540, 1548, 1552, 1680, 1684, 1692, 1696
OFFSET
1,2
COMMENTS
All the terms are multiples of 4 (A008586).
EXAMPLE
4 is a term since its factorial-base presentation, 20, has only even digits.
16 is a term since its factorial-base presentation, 220, has only even digits.
MATHEMATICA
max = 7; fctBaseDigits[n_] := IntegerDigits[n, MixedRadix[Range[max, 2, -1]]]; Select[Range[0, max!, 2], AllTrue[fctBaseDigits[#], EvenQ] &]
CROSSREFS
Subsequence: A052849 \ {2}.
Similar sequences: A005823 (ternary), A014263 (decimal), A062880 (quaternary).
Sequence in context: A374905 A253122 A239413 * A327295 A361418 A066632
KEYWORD
nonn,base
AUTHOR
Amiram Eldar, Feb 24 2022
STATUS
approved