A320108 a(n) = Product_{d|n, d>1} prime(1+(d mod 8)).

1, 5, 7, 55, 13, 595, 19, 110, 21, 325, 7, 71995, 13, 1615, 1729, 220, 3, 8925, 7, 39325, 1729, 595, 19, 287980, 39, 325, 147, 195415, 13, 12492025, 19, 440, 147, 75, 1729, 11879175, 13, 595, 1729, 157300, 3, 12492025, 7, 71995, 67431, 1615, 19, 1151920, 57, 4875, 147, 39325, 13, 1062075, 1729, 781660, 147, 325, 7, 182895738025, 13, 1615, 98553, 880, 507

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 8)).

Prog

(PARI) A320108(n) = { my(m=1); fordiv(n, d, if(d>1, m *= prime(1+(d%8)))); (m); };

Crossrefs

Cf. A080682, A319987, A320112, A320114, A320116.

Cf. A320109 (rgs-transform).

Sequence in context: A180552 A168545 A320116 * A320112 A284380 A082714

Adjacent sequences: A320105 A320106 A320107 * A320109 A320110 A320111

Keyword

nonn

Author

Antti Karttunen, Oct 06 2018

Status

approved