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A102048 Exponent of A046021(n) (least inverse of Kempner-Smarandache function A002034) when written as a power of A006530(n) (largest prime dividing n), with a(1) = 1. +0
2
1, 1, 1, 2, 1, 2, 1, 5, 3, 2, 1, 5, 1, 2, 3, 12, 1, 7, 1, 4, 3, 2, 1, 10, 5, 2, 11, 4, 1, 7, 1, 27, 3, 2, 5, 16, 1, 2, 3, 9, 1, 6, 1, 4, 10, 2, 1, 22, 7, 11, 3, 4, 1, 24, 5, 9, 3, 2, 1, 14, 1, 2, 10, 58, 5, 6, 1, 4, 3, 11, 1, 33, 1, 2, 17, 4, 7, 6, 1, 19, 37, 2, 1, 13, 5, 2, 3, 8, 1, 21, 7, 4, 3, 2, 5 (list; graph; listen)
OFFSET

1,4

COMMENT

a(n) = log(A046021(n))/log(A006530(n)) for n>1.

REFERENCES

R. L. Graham, D. E. Knuth and O. Patashnik, Factorial Factors, Section 4.4 in Concrete Mathematics, 2nd ed. Reading, MA: Addison-Wesley, pp. 111-115, 1994.

LINKS

Eric Weisstein's World of Mathematics, Link to a section of The World of Mathematics.

Eric Weisstein's World of Mathematics, Link to a section of The World of Mathematics.

Index entries for sequences related to factorial numbers.

FORMULA

1+Sum(k=1 to [log(n-1)/log(P)], [(n-1)/P^k]) for n>1, where P = A006530(n) is the greatest prime factor of n.

EXAMPLE

a(6) = 2 because A046021(6) = 9 = 3^2 = A006530(6)^2.

MATHEMATICA

With[{p=First[Last[FactorInteger[n, FactorComplete->True]]]}, 1+Sum[Floor[(n-1)/p^k], {k, Floor[Log[n-1]/Log[p]]}]]

CROSSREFS

Cf. A046021, A006530.

Sequence in context: A000001 A146002 A109087 this_sequence A102551 A152823 A086545

Adjacent sequences: A102045 A102046 A102047 this_sequence A102049 A102050 A102051

KEYWORD

nonn

AUTHOR

Jonathan Sondow (jsondow(AT)alumni.princeton.edu), Dec 26 2004

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Last modified November 25 13:47 EST 2009. Contains 167481 sequences.


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