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 A305808 Dirichlet convolution of A032742 (the largest proper divisor of n) with itself. 3
 1, 2, 2, 5, 2, 8, 2, 12, 7, 12, 2, 22, 2, 16, 12, 28, 2, 30, 2, 34, 16, 24, 2, 56, 11, 28, 24, 46, 2, 56, 2, 64, 24, 36, 16, 87, 2, 40, 28, 88, 2, 76, 2, 70, 46, 48, 2, 136, 15, 70, 36, 82, 2, 108, 24, 120, 40, 60, 2, 172, 2, 64, 62, 144, 28, 116, 2, 106, 48, 108, 2, 228, 2, 76, 70, 118, 24, 136, 2, 216, 81, 84, 2, 236, 36, 88, 60, 184, 2, 228, 28 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS Antti Karttunen, Table of n, a(n) for n = 1..65537 FORMULA a(n) = Sum_{d|n} A032742(n/d)*A032742(d). PROG (PARI) A032742(n) = if(1==n, n, n/vecmin(factor(n)[, 1])); A305808(n) = sumdiv(n, d, A032742(n/d)*A032742(d)); CROSSREFS Cf. A032742, A300236, A300239, A305807. Sequence in context: A030996 A293225 A305798 * A266662 A289078 A051612 Adjacent sequences:  A305805 A305806 A305807 * A305809 A305810 A305811 KEYWORD nonn AUTHOR Antti Karttunen, Jun 13 2018 STATUS approved

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Last modified May 25 22:17 EDT 2019. Contains 323576 sequences. (Running on oeis4.)