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 A078324 Primes of the form m*rad(m)+1, where rad = A007947 (squarefree kernel). 5
 2, 5, 17, 37, 73, 101, 109, 197, 257, 401, 433, 577, 677, 1153, 1297, 1373, 1601, 1801, 2593, 2917, 3137, 3457, 3529, 3889, 4001, 4357, 5477, 7057, 8101, 8713, 8837, 9001, 10369, 12101, 13457, 14401, 15377, 15877, 16001, 16901, 17497, 17957, 18253, 18433, 20809 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Reinhard Zumkeller, Table of n, a(n) for n = 1..1000 EXAMPLE 12*rad(12)+1 = 12*rad(3*2^2)+1 = 12*3*2+1 = 72+1 = 73, therefore 73 is a term. a(33) = 10369 = 10368 + 1: A078310(1728) = (2*3)*(2^6*3^3) = 10368. MATHEMATICA powQ[n_] := n == 1 || AllTrue[FactorInteger[n][[;; , 2]], # > 1 &]; Select[Prime[Range[2400]], powQ[# - 1] &] (* Amiram Eldar, Jul 31 2022 *) PROG (Haskell) a078324 n = a078324_list !! (n-1) a078324_list = filter ((== 1) . a010051') a224866_list -- Reinhard Zumkeller, Jul 23 2013 (PARI) is(n) = isprime(n) && ispowerful(n-1); \\ Amiram Eldar, Jul 31 2022 CROSSREFS Intersection of A000040 and A224866. Cf. A010051, A078310, A078325. Sequence in context: A100272 A107630 A078523 * A240322 A346809 A276460 Adjacent sequences: A078321 A078322 A078323 * A078325 A078326 A078327 KEYWORD nonn AUTHOR Reinhard Zumkeller, Nov 23 2002 EXTENSIONS Missing terms 10369, 16001, 17497 and 18433 inserted by Reinhard Zumkeller, Jul 23 2013 STATUS approved

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Last modified March 25 06:19 EDT 2023. Contains 361511 sequences. (Running on oeis4.)