login
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
OFFSET
1,1
COMMENTS
No two consecutive positive integers m and m+1 are both non-coprime to any particular power of a prime.
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: A340148 A049200 A347100 * A325965 A198540 A216369
KEYWORD
nonn
AUTHOR
Leroy Quet, Aug 22 2009
EXTENSIONS
Extended by Ray Chandler, Mar 15 2010
STATUS
approved