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A320114 a(n) = Product_{d|n, d>1} prime(1+(d mod 4)). 6
1, 5, 7, 10, 3, 175, 7, 20, 21, 75, 7, 700, 3, 175, 147, 40, 3, 2625, 7, 300, 147, 175, 7, 2800, 9, 75, 147, 700, 3, 91875, 7, 80, 147, 75, 147, 21000, 3, 175, 147, 1200, 3, 91875, 7, 700, 1323, 175, 7, 11200, 21, 1125, 147, 300, 3, 91875, 147, 2800, 147, 75, 7, 1470000, 3, 175, 3087, 160, 27, 91875, 7, 300, 147, 91875, 7, 168000, 3, 75 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Antti Karttunen, Table of n, a(n) for n = 1..8192

FORMULA

a(n) = Product_{d|n, d>1} prime(1+(d mod 4)).

MAPLE

with(numtheory): P:=proc(n) local a, d; a:=divisors(n) minus {1};

mul(ithprime(1+(d mod 4)), d=a); end: seq(P(i), i=1..74); # Paolo P. Lava, Oct 11 2018

PROG

(PARI) A320114(n) = { my(m=1); fordiv(n, d, if(d>1, m *= prime(1+(d%4)))); (m); };

CROSSREFS

Cf. A320115 (rgs-transform), A320116.

Cf. also A319984.

Cf. A002144 (a(n)=3), A002145 (a(n)=7).

Sequence in context: A050888 A323004 A264349 * A059485 A028786 A282391

Adjacent sequences:  A320111 A320112 A320113 * A320115 A320116 A320117

KEYWORD

nonn

AUTHOR

Antti Karttunen, Oct 06 2018

STATUS

approved

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Last modified June 17 16:49 EDT 2021. Contains 345085 sequences. (Running on oeis4.)