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A266265
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Product of products of divisors of divisors of n.
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11
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1, 2, 3, 16, 5, 216, 7, 1024, 81, 1000, 11, 2985984, 13, 2744, 3375, 1048576, 17, 34012224, 19, 64000000, 9261, 10648, 23, 63403380965376, 625, 17576, 59049, 481890304, 29, 19683000000000, 31, 34359738368, 35937, 39304, 42875, 4738381338321616896, 37, 54872
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OFFSET
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1,2
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COMMENTS
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a(n) = Product_{d|n} A007955(d) where A007955(m) = product of divisors of m.
for n>=1: 10^3|a(10*n), 10^6|a(20*n), 10^9|a(30*n).
for n>=0: 10^6|a(60*n+50), 10^9|a(60*n+70). (End)
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LINKS
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FORMULA
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a(p) = p for p = prime.
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EXAMPLE
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For n = 6; with b(n) = A007955(n); a(6) = b(1)*b(2)*b(3)*b(6) = 1*2*3*36 = 216.
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MAPLE
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mul( A007955(d), d=numtheory[divisors](n)) ;
end proc:
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MATHEMATICA
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Table[Product[Times @@ Divisors@ d, {d, Divisors@ n}], {n, 38}] (* Michael De Vlieger, Dec 31 2015 *)
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PROG
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(Magma) [&*[&*[b: b in Divisors(d)]: d in Divisors(n)]: n in [1..100]]
(PARI) a(n) = {my(d = divisors(n)); prod(k=1, #d, dd = divisors(d[k]); prod(kk=1, #dd, dd[kk])); } \\ Michel Marcus, Dec 27 2015
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CROSSREFS
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Cf. A007955 (product of divisors of n), A175317 (sum of products of divisors of divisors of n), A206032 (product of sums of divisors of divisors of n).
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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