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A112779
Largest exponent in the prime factorization of highly composite numbers (definition 1, A002182).
11
0, 1, 2, 1, 2, 3, 2, 4, 2, 3, 2, 4, 3, 4, 3, 2, 4, 3, 4, 3, 5, 4, 6, 4, 3, 4, 5, 4, 3, 5, 4, 6, 4, 5, 4, 5, 6, 4, 3, 5, 4, 6, 4, 5, 4, 5, 6, 4, 6, 7, 5, 4, 4, 6, 4, 5, 4, 5, 6, 4, 6, 7, 5, 4, 4, 6, 5, 5, 4, 6, 5, 6, 4, 6, 7, 5, 4, 6, 5, 7, 6, 5, 6, 4, 4, 6, 7, 5, 5, 4, 6, 6, 5, 7, 6, 5, 6, 4, 7, 6, 7, 5, 7, 6, 8
OFFSET
1,3
COMMENTS
Each highly composite number can be written as the product of primorials (A002110); a(n) is also the number of primorials used in the product.
a(i) is the exponent of 2 in the prime factorization of A002182(i), cf. formula. - David A. Corneth, Aug 16 2015; edited by M. F. Hasler, Jan 03 2020
LINKS
T. D. Noe, Table of n, a(n) for n=1..10000 (using Flammenkamp's data)
Eric Weisstein's World of Mathematics, Highly Composite Number
FORMULA
a(n) = A007814(A002182(n)). - David A. Corneth, Aug 16 2015
EXAMPLE
A002182(8) = 48 = 2^4*3, which has largest exponent 4, so a(8)=4.
PROG
(PARI) apply( A112779(n)=valuation(A002182(n), 2), [1..99]) \\ M. F. Hasler, Jan 03 2020
KEYWORD
nonn
AUTHOR
Ray Chandler, Nov 11 2005
STATUS
approved