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A338083
Primes p such that p+2 is prime and the sum of prime factors of p+1 (taken with repetition) is prime.
2
5, 11, 107, 197, 419, 431, 461, 521, 569, 599, 659, 809, 857, 1019, 1061, 1277, 1289, 1301, 1427, 1451, 1481, 1721, 1931, 2087, 2267, 3119, 3467, 3539, 4019, 4157, 4217, 4241, 4259, 4421, 5279, 5639, 5651, 5849, 5867, 6359, 6689, 6869, 7127, 7331, 7349, 7487, 7547, 7757, 8219, 8819, 8837, 8861
OFFSET
1,1
LINKS
EXAMPLE
a(3)=107 is a term because 107 and 109 are prime while 108=2^2*3^3 and 2*2+3*3=13 is prime.
MAPLE
TP:= select(t -> isprime(t) and isprime(t+2), [seq(i, i=5..1000, 6)]):
select(p -> isprime(add(t[1]*t[2], t=ifactors(p+1)[2])), TP);
MATHEMATICA
Select[Partition[Prime[Range[1250]], 2, 1], #[[2]]-#[[1]]==2&&PrimeQ[Total[ Times@@@ FactorInteger[#[[1]]+1]]]&][[All, 1]] (* Harvey P. Dale, Jul 10 2022 *)
CROSSREFS
Intersection of A001359 and A127269.
Sequence in context: A090160 A062652 A075706 * A236509 A330488 A057178
KEYWORD
nonn
AUTHOR
Robert Israel, Oct 08 2020
STATUS
approved