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A250047 Numbers n such that m = floor(n/7) is not coprime to n and, if nonzero, m is also a term of the sequence. 11
2, 3, 4, 5, 6, 14, 16, 18, 20, 21, 24, 27, 28, 30, 32, 34, 35, 40, 42, 44, 45, 46, 48, 98, 100, 102, 104, 112, 114, 116, 118, 126, 128, 129, 130, 132, 140, 142, 144, 145, 146, 147, 150, 153, 168, 170, 171, 172, 174, 189, 192, 195, 196, 198, 200, 202, 210 (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=7. In particular, they define the property RTNC(b).
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=7) = {while (((m=gcd(n\b, n)) != 1), if (m == 0, return (1)); n = n\b; ); return (0); } \\ Michel Marcus, Jan 22 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), A250049 (b=6), A250051 (b=5).
Sequence in context: A334733 A039016 A249102 * A084830 A116044 A116027
KEYWORD
nonn,base
AUTHOR
Stanislav Sykora, Jan 15 2015
STATUS
approved

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Last modified February 26 12:54 EST 2024. Contains 370352 sequences. (Running on oeis4.)