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A250039
Numbers n such that m = floor(n/16) is not coprime to n and, if nonzero, m is also a term of the sequence.
9
2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 32, 34, 36, 38, 40, 42, 44, 46, 48, 51, 54, 57, 60, 63, 64, 66, 68, 70, 72, 74, 76, 78, 80, 85, 90, 95, 96, 98, 99, 100, 102, 104, 105, 106, 108, 110, 111, 112, 119, 126, 128, 130, 132, 134, 136, 138, 140, 142
OFFSET
1,1
COMMENTS
See the comments in A250041 which all apply, except for the setting of the base, b=16. In particular, they define the property RTNC(b).
This list is an infinite subset of A248502 with which it shares the first 111 entries.
LINKS
Stanislav Sykora, PARI/GP scripts for genetic threads, with code and comments.
Wikipedia, Coprime integers
PROG
(PARI) See the link.
(PARI) is_rtnc(n, b=16) = {while (((m=gcd(n\b, n)) != 1), if (m == 0, return (1)); n = n\b; ); return (0); } \\ Michel Marcus, Jan 29 2015
CROSSREFS
Other lists of right-truncatable numbers with the property RTNC(b): A005823 (b=3), A250037 (b=4), A250041 (b=10), A250043 (b=9), A250045 (b=8), A250047 (b=7), A250049 (b=6), A250051 (b=5).
Sequence in context: A365684 A309127 A248502 * A132032 A341709 A055645
KEYWORD
nonn,base
AUTHOR
Stanislav Sykora, Dec 07 2014
STATUS
approved