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A140255
Inverse Mobius transform of A014963.
6
1, 3, 4, 5, 6, 7, 8, 7, 7, 9, 12, 10, 14, 11, 10, 9, 18, 11, 20, 12, 12, 15, 24, 13, 11, 17, 10, 14, 30, 15, 32, 11, 16, 21, 14, 15, 38, 23, 18, 15, 42, 17, 44, 18, 14, 27, 48, 16, 15, 15, 22, 20, 54, 15, 18, 17, 24, 33, 60, 20, 62, 35, 16, 13, 20, 21, 68, 24, 28, 19, 72, 19, 74
OFFSET
1,2
FORMULA
A051731 as an infinite lower triangular matrix * A014963 as a vector.
Equals row sums of triangle A140256. - Gary W. Adamson, May 16 2008
G.f.: Sum_{k>=1} M(k)*x^k/(1 - x^k), where M(k) is the exponential of Mangoldt function (A014963). - Ilya Gutkovskiy, Jan 16 2017
EXAMPLE
a(4) = 5 = (1, 1, 0, 1) dot (1, 2, 3, 2) = (1 + 2 + 0 + 2); where (1, 1, 0, 1) = row 4 of triangle A051731 and (1, 2, 3, 2) = the first 4 terms of A014963.
PROG
(PARI)
expmangoldt(n)=ispower(n, , &n); if(isprime(n), n, 1);
a(n) = sumdiv(n, d, expmangoldt(d)) \\ Jodi Spitz, Apr 11 2023
CROSSREFS
KEYWORD
nonn
AUTHOR
Gary W. Adamson and Mats Granvik, May 16 2008
EXTENSIONS
More terms from R. J. Mathar, Jan 19 2009
STATUS
approved