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 A351894 Numbers that contain only odd digits in their factorial-base representation. 4
 1, 3, 9, 21, 33, 45, 81, 93, 153, 165, 201, 213, 393, 405, 441, 453, 633, 645, 681, 693, 873, 885, 921, 933, 1113, 1125, 1161, 1173, 1353, 1365, 1401, 1413, 2313, 2325, 2361, 2373, 2553, 2565, 2601, 2613, 2793, 2805, 2841, 2853, 3753, 3765, 3801, 3813, 3993, 4005 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS All the terms above 1 are odd multiples of 3. LINKS Amiram Eldar, Table of n, a(n) for n = 1..18056 (terms below 11!) Wikipedia, Factorial number system. EXAMPLE 3 is a term since its factorial-base presentation, 11, has only odd digits. 21 is a term since its factorial-base presentation, 311, has only odd digits. MATHEMATICA max = 7; fctBaseDigits[n_] := IntegerDigits[n, MixedRadix[Range[max, 2, -1]]]; Select[Range[1, max!, 2], AllTrue[fctBaseDigits[#], OddQ] &] CROSSREFS Cf. A007623, A016945, A351893. Subsequence: A007489 Similar sequences: A003462 \ {0} (ternary), A014261 (decimal), A032911 (base 4), A032912 (base 5), A033032 (base 6), A033033 (base 7), A033034 (base 8), A033035 (base 9), A033036 (base 11), A033037 (base 12), A033038 (base 13), A033039 (base 14), A033040 (base 15), A033041 (base 16), A126646 (binary). Sequence in context: A331131 A089322 A182632 * A286590 A061978 A031886 Adjacent sequences:  A351891 A351892 A351893 * A351895 A351896 A351897 KEYWORD nonn,base AUTHOR Amiram Eldar, Feb 24 2022 STATUS approved

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Last modified August 15 02:13 EDT 2022. Contains 356122 sequences. (Running on oeis4.)