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A097379
Numbers m such that 1+SquareFreeKernel(m) is prime.
6
1, 2, 4, 6, 8, 10, 12, 16, 18, 20, 22, 24, 30, 32, 36, 40, 42, 44, 46, 48, 50, 54, 58, 60, 64, 66, 70, 72, 78, 80, 82, 84, 88, 90, 92, 96, 100, 102, 106, 108, 116, 120, 126, 128, 130, 132, 138, 140, 144, 150, 156, 160, 162, 164, 166, 168, 176, 178, 180, 184, 190, 192
OFFSET
1,2
LINKS
FORMULA
A076618(a(n)) = A007947(a(n))+1 is prime.
EXAMPLE
m = 100 = (2*5)^2 -> A076618(100) = 1+2*5 = 11 = A000040(5), therefore 100 is a term.
MATHEMATICA
Select[Range[200], PrimeQ[1 + Times @@ FactorInteger[#][[;; , 1]]] &] (* Amiram Eldar, Feb 01 2024 *)
PROG
(PARI) is(n) = isprime(1 + vecprod(factor(n)[, 1])); \\ Amiram Eldar, Feb 01 2024
CROSSREFS
KEYWORD
nonn
AUTHOR
Reinhard Zumkeller, Aug 11 2004
STATUS
approved