A250039 - OEIS

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.

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

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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, 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 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

Cf. A248502, A250038, A250041.

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

Adjacent sequences: A250036 A250037 A250038 * A250040 A250041 A250042

KEYWORD

nonn,base

AUTHOR

Stanislav Sykora, Dec 07 2014

STATUS

approved