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A250043 Numbers n such that m = floor(n/9) is not coprime to n and, if nonzero, m is also a term of the sequence. 9
2, 3, 4, 5, 6, 7, 8, 18, 20, 22, 24, 26, 27, 30, 33, 36, 38, 40, 42, 44, 45, 50, 54, 56, 57, 58, 60, 62, 63, 70, 72, 74, 76, 78, 80, 162, 164, 165, 166, 168, 170, 180, 182, 184, 185, 186, 188, 198, 200, 202, 204, 206, 216, 218, 219, 220, 222, 224, 234, 236 (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=9. 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 the link

(PARI) is_rtnc(n, b=9) =  {while (((m=gcd(n\b, n)) != 1), if (m == 0, return (1)); n = n\b; ); return (0); } \\ Michel Marcus, Jan 17 2015

CROSSREFS

Cf. A250041 (b=10), A250042.

Other lists of right-truncatable numbers with the property RTNC(b): A005823 (b=3), A250037 (b=4), A250039 (b=16),  A250045 (b=8), A250047 (b=7), A250049 (b=6), A250051 (b=5).

Sequence in context: A204928 A171723 A039050 * A260354 A114799 A055557

Adjacent sequences:  A250040 A250041 A250042 * A250044 A250045 A250046

KEYWORD

nonn,base

AUTHOR

Stanislav Sykora, Jan 15 2015

STATUS

approved

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Last modified August 20 03:34 EDT 2017. Contains 290823 sequences.