A137698 a(1)=2. a(n) = the smallest integer > a(n-1) that is not in sequence A137699. A137699(n) = the smallest integer > A137698(n) and not coprime to A137698(n). (A137699(n) = A137698(n) + smallest prime dividing A137698(n).).

2, 3, 5, 7, 8, 9, 11, 13, 15, 16, 17, 19, 20, 21, 23, 25, 27, 28, 29, 31, 32, 33, 35, 37, 39, 41, 43, 44, 45, 47, 49, 50, 51, 53, 55, 57, 59, 61, 63, 64, 65, 67, 68, 69, 71, 73, 75, 76, 77, 79, 80, 81, 83, 85, 87, 88, 89, 91, 92, 93, 95, 97

Offset

1,1

Links

Table of n, a(n) for n=1..62.

Example

Checking for the value of a(17): a(16) = 25. Checking 26, we see that A137699(8) = 26 (because a(8) = 13 and 26 is the smallest integer > 13 that is not coprime to 13). So a(17) does not equal 26. 27, however, does not occur in sequence A137699. So a(17) = 27.

Crossrefs

Cf. A137699.

Sequence in context: A062062 A256133 A078643 * A358978 A063743 A353968

Adjacent sequences: A137695 A137696 A137697 * A137699 A137700 A137701

Keyword

easy,nonn

Author

Leroy Quet, Feb 06 2008

Extensions

More terms from Sean A. Irvine, Feb 12 2012

Status

approved