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A182908 Rank of 2^n when all prime powers p^n, for n>=1, are jointly ranked. 2
1, 3, 6, 10, 18, 27, 44, 70, 117, 198, 340, 604, 1078, 1961, 3590, 6635, 12370, 23150, 43579, 82267, 155921, 296347, 564688, 1078555, 2064589, 3958999, 7605134, 14632960, 28195586, 54403835, 105102701, 203287169, 393625231, 762951922 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

A182908(n)=-1+A024622(n) for n>=1.  Row 1 of A182869.  Complement of A182909.

LINKS

Table of n, a(n) for n=1..34.

EXAMPLE

a(3)=6 because 2^3 has rank 6 in the sequence (2,3,4,5,7,8,9,...).

MATHEMATICA

T[i_, j_]:=Sum[Floor[j*Log[Prime[i]]/Log[Prime[h]]], {h, 1, PrimePi[Prime[i]^j]}]; Table[Flatten[Table[T[i, j], {i, 1, 1}, {j, 1, 22}]]]

f[n_] := Sum[ PrimePi[ Floor[10^(n/k)]], {k, n + 1}]; Array[f, 34] (* Robert G. Wilson v, Jul 08 2011 *)

CROSSREFS

Cf. A000961, A182869, A024622, A182909.

Sequence in context: A291608 A182152 A170803 * A076251 A261631 A029864

Adjacent sequences:  A182905 A182906 A182907 * A182909 A182910 A182911

KEYWORD

nonn

AUTHOR

Clark Kimberling, Dec 13 2010

STATUS

approved

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Last modified February 20 21:16 EST 2019. Contains 320350 sequences. (Running on oeis4.)