A182909 Ranks of composite numbers when all prime powers p^n for n>=1 are jointly ranked.

3, 6, 7, 10, 14, 15, 18, 23, 27, 32, 41, 42, 44, 53, 68, 70, 78, 86, 91, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 141, 142

Offset

1,1

Comments

The complement of A027883.

Links

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

Example

In the sequence A000961 (2,3,4,5,7,8,9,11,13,16,
17,19,23,25,27,...) of prime powers p^n for n>=1, the
composites 4,8,9,16,25,27,... occur with ranks
3,6,7,10,14,15...

Mathematica

T[i_, j_]:=Sum[Floor[j*Log[Prime[i]]/Log[Prime[h]]], {h, 1, PrimePi[Prime[i]^j]}]; Complement[Range[200], Table[Flatten[Table[T[i, j], {i, 1, 80}, {j, 1, 1}]]]

Crossrefs

Cf. A000961, A024620, A027883.

Sequence in context: A288215 A284625 A047281 * A269903 A191103 A100468

Adjacent sequences: A182906 A182907 A182908 * A182910 A182911 A182912

Keyword

nonn

Author

Clark Kimberling, Dec 13 2010

Status

approved