A025006 a(1) = 7; a(n+1) = a(n)-th nonprime, where nonprimes begin at 1.

7, 12, 20, 30, 44, 62, 85, 115, 150, 194, 247, 310, 386, 477, 583, 710, 858, 1030, 1232, 1464, 1734, 2043, 2400, 2809, 3270, 3798, 4396, 5073, 5838, 6702, 7675, 8768, 9997, 11370, 12905, 14615, 16528, 18658, 21024, 23655, 26570, 29798, 33372, 37324, 41685

Offset

1,1

Links

Table of n, a(n) for n=1..45.

Mathematica

With[{np=Select[Range[100000], !PrimeQ[#]&]}, NestList[np[[#]]&, 7, 50]] (* Harvey P. Dale, Apr 06 2018 *)

Crossrefs

Sequence in context: A271988 A093330 A071247 * A189321 A273072 A273147

Adjacent sequences: A025003 A025004 A025005 * A025007 A025008 A025009

Keyword

nonn

Author

David W. Wilson

Status

approved