A078695 a(n+1) = a(n)+greatest prime divisor of a(n-1).

1, 1, 2, 3, 5, 8, 13, 15, 28, 33, 40, 51, 56, 73, 80, 153, 158, 175, 254, 261, 388, 417, 514, 653, 910, 1563, 1576, 2097, 2294, 2527, 2564, 2583, 3224, 3265, 3296, 3949, 4052, 4411, 5424, 5825, 5938, 6171, 9140, 9157, 9614, 18771, 18794, 25051, 34448, 34495

Offset

1,3

Links

Harvey P. Dale, Table of n, a(n) for n = 1..1000

Example

a(12) = 51 = 3*17, a(13) = 56, so a(14) = 56+17 = 73

Mathematica

nxt[{a_, b_}]:={b, b+FactorInteger[a][[-1, 1]]}; Transpose[NestList[nxt, {1, 1}, 50]][[1]] (* Harvey P. Dale, Jan 15 2016 *)

Crossrefs

Cf. A000045.

Sequence in context: A182444 A138183 A076591 * A121367 A308495 A221672

Adjacent sequences: A078692 A078693 A078694 * A078696 A078697 A078698

Keyword

easy,nonn

Author

Miklos Kristof, Dec 18 2002

Extensions

More terms from Robert G. Wilson v, Dec 19 2002

Status

approved