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 A179307 a(n) = Sum_{d|n} C(n,d)*sigma(d)*sigma(n/d). 1
 1, 9, 16, 89, 36, 504, 64, 2193, 1474, 5544, 144, 56024, 196, 84912, 83376, 674257, 324, 2833128, 400, 10842624, 3764224, 25404696, 576, 283622136, 1913486, 436839984, 243868120, 2955876880, 900, 13385040624, 1024, 57008721777 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS FORMULA Logarithmic derivative of A179306. PROG (PARI) {a(n)=sumdiv(n, d, binomial(n, d)*sigma(d)*sigma(n/d))} CROSSREFS Cf. A179306. Sequence in context: A267763 A340164 A308248 * A014720 A138238 A177171 Adjacent sequences:  A179304 A179305 A179306 * A179308 A179309 A179310 KEYWORD nonn AUTHOR Paul D. Hanna, Jul 10 2010 STATUS approved

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Last modified December 4 15:36 EST 2021. Contains 349526 sequences. (Running on oeis4.)