A066996 Numbers n such that Sum_{i=2..n} 1/A001221(i) is an integer.

2, 3, 4, 5, 10, 11, 14, 18, 19, 21, 24, 25, 28, 29, 62, 65, 80, 81, 102, 103, 115, 117, 119, 130, 131, 140, 142, 144, 146, 148, 149, 158, 160, 162, 163, 170, 172, 173, 182, 184, 195, 341, 348, 349, 357, 366, 367, 369, 375, 377, 386, 388, 389, 426, 428, 441, 450

Offset

1,1

Links

Harry J. Smith, Table of n, a(n) for n = 1..1000

Mathematica

Select[Range[2, 1000], IntegerQ[Sum[1/PrimeNu[k], {k, 2, #}]] &] (* G. C. Greubel, Apr 23 2017 *)

Prog

(PARI) { n=0; a=0; for (m=2, 10^10, a+=1/omega(m); if (a % 1.0 == 0 , write("b066996.txt", n++, " ", m); if (n==1000, return)) ) } \\ Harry J. Smith, Apr 24 2010

Crossrefs

Sequence in context: A210495 A179302 A240083 * A126427 A032860 A032884

Adjacent sequences: A066993 A066994 A066995 * A066997 A066998 A066999

Keyword

nonn

Author

Benoit Cloitre, Jan 27 2002

Extensions

Missing terms a(22)=117 and a(24)=130 added by Harry J. Smith, Apr 24 2010

Status

approved