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 A250051 Numbers n such that m = floor(n/5) is not coprime to n and, if nonzero, m is also a term of the sequence. 8
 2, 3, 4, 10, 12, 14, 15, 18, 20, 22, 24, 50, 52, 54, 60, 62, 63, 64, 70, 72, 74, 75, 78, 90, 92, 93, 94, 100, 102, 104, 110, 112, 114, 120, 122, 123, 124, 250, 252, 254, 260, 262, 264, 270, 272, 273, 274, 300, 302, 303, 304, 310, 312, 314, 315, 318 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS See the comments in A250041 which all apply, except for the setting of the base, b=5. In particular, they define the property RTNC(b). LINKS Stanislav Sykora, Table of n, a(n) for n = 1..10000 Stanislav Sykora, PARI/GP scripts for genetic threads, with code and comments. Wikipedia, Coprime integers PROG (PARI) \\ See A250041 for b=5 (PARI) is_rtnc(n, b=5) = {while (((m=gcd(n\b, n)) != 1), if (m == 0, return (1)); n = n\b; ); return (0); } \\ Michel Marcus, Jan 31 2015 CROSSREFS Cf. A250041 (b=10), A250046. Other lists of right-truncatable numbers with the property RTNC(b): A005823 (b=3), A250037 (b=4), A250039 (b=16), A250043 (b=9), A250045 (b=8), A250047 (b=7), A250049 (b=6). Sequence in context: A085701 A051627 A023725 * A076079 A229593 A196007 Adjacent sequences:  A250048 A250049 A250050 * A250052 A250053 A250054 KEYWORD nonn,base AUTHOR Stanislav Sykora, Jan 31 2015 STATUS approved

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Last modified December 17 12:03 EST 2018. Contains 318200 sequences. (Running on oeis4.)