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A244959
Smallest positive multiple of n whose base 8 representation contains only 0's and 1's.
2
1, 8, 9, 8, 65, 72, 299593, 8, 9, 520, 4169, 72, 65, 2396744, 585, 64, 4097, 72, 513, 520, 17044041, 33352, 33281, 72, 266825, 520, 513, 2396744, 266249, 4680, 4681, 64, 32769, 32776, 16814665, 72, 262145, 4104, 585, 520, 32841, 136352328, 36937, 33352, 585
OFFSET
1,2
LINKS
Ed Pegg Jr., 'Binary' Puzzle
Eric M. Schmidt, Sage code to compute this sequence (use b=8)
Chai Wah Wu, Pigeonholes and repunits, Amer. Math. Monthly, 121 (2014), 529-533.
MATHEMATICA
Module[{nn=10, b8}, b8=Rest[FromDigits[#, 8]&/@Tuples[{0, 1}, nn]]; Table[SelectFirst[ b8, Mod[#, n]==0&], {n, 100}]] (* Harvey P. Dale, Feb 03 2024 *)
PROG
(Python)
def A244959(n):
....if n > 0:
........for i in range(1, 2**n):
............x = int(bin(i)[2:], 8)
............if not x % n:
................return x
....return 0 # Chai Wah Wu, Dec 30 2014
CROSSREFS
Cf. A004288 (written in base 8), A004290, A244954-A244960.
Sequence in context: A019606 A010732 A235398 * A377999 A345987 A241990
KEYWORD
nonn,base
AUTHOR
Eric M. Schmidt, Jul 09 2014
EXTENSIONS
Data corrected, offset corrected, and b-file replaced by Harvey P. Dale, Feb 03 2024
STATUS
approved