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A275700
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a(n) = Product_{d|n} prime(d).
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9
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2, 6, 10, 42, 22, 390, 34, 798, 230, 1914, 62, 101010, 82, 4386, 5170, 42294, 118, 547170, 134, 951258, 12410, 14694, 166, 170807910, 2134, 24846, 23690, 3285114, 218, 660741510, 254, 5540514, 42470, 49206, 55726, 21399271530, 314, 65526, 68470, 3126785046, 358
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OFFSET
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1,1
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COMMENTS
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a(n) mod n = 0 for n: 1, 2, 6, 30, 78, 330, 390, 870, 1410, 3198, ...
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LINKS
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EXAMPLE
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a(4) = 42 because the divisors of 4 are: 1, 2 and 4; and prime(1) * prime(2) * prime(4) = 2 * 3 * 7 = 42.
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MATHEMATICA
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Table[Times@@(Prime[#]&/@Divisors[n]), {n, 50}] (* Harvey P. Dale, Jun 16 2017 *)
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PROG
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(Magma) [(&*[NthPrime(d): d in Divisors(n)]): n in [1..100]]
(PARI) a(n) = my(d=divisors(n)); prod(i=1, #d, prime(d[i])) \\ Felix Fröhlich, Aug 05 2016
(Perl) use ntheory ":all"; sub a275700 { vecprod(map { nth_prime($_) } divisors($_[0])); } # Dana Jacobsen, Aug 09 2016
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CROSSREFS
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A version for binary indices is A034729.
Partitions of this type are counted by A054973, strict case of A371284.
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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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