A120797 a(0) = 1. a(n) = n + (largest noncomposite {1 or prime} occurring earlier in the sequence).

1, 2, 4, 5, 9, 10, 11, 18, 19, 28, 29, 40, 41, 54, 55, 56, 57, 58, 59, 78, 79, 100, 101, 124, 125, 126, 127, 154, 155, 156, 157, 188, 189, 190, 191, 226, 227, 264, 265, 266, 267, 268, 269, 312, 313, 358, 359, 406, 407, 408, 409, 460, 461, 514, 515, 516, 517, 518

Offset

0,2

Links

Table of n, a(n) for n=0..57.

Example

Among terms a(0) through a(9), a(8) = 19 is the largest noncomposite. So a(10) = 10 + 19 = 29.

Mathematica

s={1}; Do[AppendTo[s, n+Max[Select[s, !CompositeQ[#]&]]], {n, 57}]; s (* James C. McMahon, Oct 09 2024 *)

Prog

(PARI) {m=58; print1(a=1, ", "); v=[a]; for(n=1, m, v=vecsort(v); j=#v; a=0; while(a<1, k=v[j]; if(isprime(k)||k==1, print1(a=n+k, ", "); v=concat(v, a), j--)))} \\ Klaus Brockhaus, Aug 17 2006

Crossrefs

Sequence in context: A072795 A189099 A189658 * A284389 A342735 A342750

Adjacent sequences: A120794 A120795 A120796 * A120798 A120799 A120800

Keyword

nonn

Author

Leroy Quet, Jul 05 2006

Extensions

More terms from Klaus Brockhaus, Aug 17 2006

Status

approved