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 A216482 a(n) is the least value of k such that k*n uses only digits 1 and 2. a(n) = -1 if no such multiple exists. 0
 1, 1, 4, 3, -1, 2, 3, 14, 1358, -1, 1, 1, 17, 8, -1, 7, 13, 679, 59, -1, 1, 1, 527, 88, -1, 47, 786, 4, 418, -1, 362, 66, 34, 33, -1, 617, 3, 319, 2849, -1, 271, 291, 284, 48, -1, 2657, 26, 44, 229, -1, 22, 406, 4, 393, -1, 2, 3723, 209, 19, -1, 2, 181, 194, 33, -1, 17, 33, 1634, 3219, -1, 172, 1696, 2907, 3, -1, 1462, 1443, 1554, 28, -1, 262, 271, 134, 1443 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 LINKS CROSSREFS Cf. A004290, A079339, A181060, A181061. Sequence in context: A189967 A139623 A278072 * A080758 A123683 A010306 Adjacent sequences:  A216479 A216480 A216481 * A216483 A216484 A216485 KEYWORD sign,base AUTHOR V. Raman, Sep 07 2012 STATUS approved

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Last modified October 25 01:18 EDT 2020. Contains 338010 sequences. (Running on oeis4.)