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A164701 a(n) = the smallest positive integer such that neither a(n) nor a(n)+1 are coprime to A024619(n), where A024619 is the sequence of positive integers that are not powers of primes. 0
2, 4, 2, 6, 5, 2, 4, 6, 10, 2, 12, 6, 2, 11, 16, 14, 2, 18, 12, 4, 2, 10, 5, 22, 2, 4, 17, 12, 2, 10, 6, 18, 28, 2, 30, 6, 25, 2, 16, 23, 4, 2, 36, 5, 18, 21, 2, 4, 40, 2, 34, 42, 29, 10, 2, 13, 22, 30, 46, 19, 2, 6, 11, 4, 2, 12, 5, 52, 2, 4, 36, 6, 2, 45, 28, 12, 58, 34, 2, 60, 41, 30, 2 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

No two consecutive positive integers m and m+1 are both non-coprime to any particular power of a prime.

LINKS

Table of n, a(n) for n=1..83.

EXAMPLE

22 is the 9th positive integer that is not a power of a prime. a(9) = 10 because neither 10 nor 10+1=11 is coprime to 22, and 10 and 11 are the smallest pair of consecutive positive integers where this is the case.

CROSSREFS

Cf. A024619.

Sequence in context: A322071 A176342 A049200 * A198540 A216369 A083791

Adjacent sequences:  A164698 A164699 A164700 * A164702 A164703 A164704

KEYWORD

nonn

AUTHOR

Leroy Quet, Aug 22 2009

EXTENSIONS

Extended by Ray Chandler, Mar 15 2010

STATUS

approved

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Last modified April 20 14:27 EDT 2019. Contains 322310 sequences. (Running on oeis4.)