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A250036 Numbers n such that m = floor(n/4) is coprime to n and, if nonzero, m is also a term of the sequence. 9
1, 4, 5, 6, 7, 17, 19, 21, 22, 23, 25, 29, 30, 31, 69, 70, 71, 77, 78, 79, 85, 86, 89, 91, 93, 94, 95, 101, 102, 103, 117, 118, 119, 121, 125, 126, 127, 277, 278, 281, 283, 285, 286, 287, 309, 310, 311, 313, 317, 318, 319, 341, 342, 343, 345, 347, 357, 358 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

See the comments in A250040 which all apply, except for the setting of the base, b=4. In particular, they define the property RTC(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_rtc(n, b=4) =  {while (((m=gcd(n\b, n)) == 1), if (m == 0, return (1)); if ((n=n\b) == 0, return (1)); ); return (0); } \\ Michel Marcus, Jan 18 2015

CROSSREFS

Cf. A250037, A250040.

Other lists of right-truncatable numbers with the property RTC(b): A250038 (b=16), A250040 (b=10), A250042 (b=9), A250044 (b=8), A250046 (b=7), A250048 (b=6), A250050 (b=5).

Sequence in context: A053738 A154787 A233035 * A107759 A161627 A030667

Adjacent sequences:  A250033 A250034 A250035 * A250037 A250038 A250039

KEYWORD

nonn,base

AUTHOR

Stanislav Sykora, Dec 07 2014

STATUS

approved

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Last modified August 21 04:27 EDT 2017. Contains 290858 sequences.