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 A215251 Product of terms in n-th row of A037306. 2
 1, 1, 1, 2, 4, 36, 225, 7840, 313600, 45302400, 8930250000, 8373836401920, 9001015156742400, 41813367543204433176, 325385777102562972821025, 8270190445766978650521600000, 377177413291384771899817984000000, 62187743659065606074696974956949929984 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,4 COMMENTS Also products of terms in rows of A047996. REFERENCES R. Bekes, J. Pedersen and B. Shao, Mad tea party cyclic partitions, College Math. J., 43 (2012), 24-36. LINKS Alois P. Heinz, Table of n, a(n) for n = 1..50 MAPLE with (numtheory): a:= n-> mul (add(phi(d)*binomial(n/d, k/d),                      d=divisors(igcd(n, k))), k=0..n)/n^(n+1): seq (a(n), n=1..20);  # Alois P. Heinz, Sep 06 2012 MATHEMATICA t[n_, k_] := Total[EulerPhi[#] * Binomial[n/#, k/#]& /@ Divisors[GCD[n, k]]]/n; Table[Times @@ Table[t[n, k], {k, 1, n}], {n, 1, 18}] (* Jean-François Alcover, Mar 07 2014 *) CROSSREFS Cf. A037306, A008965, A047996. Sequence in context: A182965 A189002 A304558 * A052716 A081976 A326932 Adjacent sequences:  A215248 A215249 A215250 * A215252 A215253 A215254 KEYWORD nonn,easy AUTHOR N. J. A. Sloane, Sep 05 2012 STATUS approved

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Last modified June 7 05:20 EDT 2020. Contains 334837 sequences. (Running on oeis4.)