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A339437
Numbers k such that A339436(k) is prime.
2
6, 10, 22, 34, 58, 82, 118, 142, 202, 214, 216, 252, 274, 298, 330, 358, 382, 390, 394, 454, 468, 478, 490, 538, 562, 588, 622, 684, 690, 694, 726, 798, 838, 858, 862, 870, 910, 922, 924, 1042, 1044, 1122, 1138, 1176, 1198, 1210, 1224, 1234, 1254, 1282, 1290, 1318, 1332, 1440, 1482, 1518, 1540
OFFSET
1,1
COMMENTS
All terms are even.
LINKS
EXAMPLE
a(15)=330 is a member because 330 = 2*3*5*11 and A339436(330) = 2 + 2*3 + 2*3*5 + 3*5*11 + 5*11 + 11 = 269 is prime.
MAPLE
A339436:= proc(n) local L, m;
L:= sort(map(t -> t[1]$t[2], ifactors(n)[2]));
m:= nops(L);
add(mul(L[i], i=1..j)+mul(L[i], i=j+1..m), j=1..m-1)
end proc:
select(isprime @ A339436, [seq(i, i=2 .. 10000, 2)]);
CROSSREFS
Includes A108605. Disjoint from A014612.
Cf. A339436.
Sequence in context: A255746 A082917 A001172 * A108605 A216049 A063765
KEYWORD
nonn
AUTHOR
J. M. Bergot and Robert Israel, Dec 04 2020
STATUS
approved