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 A023339 Numbers n such that n remains prime through 5 iterations of function f(x) = 4x + 3. 1
 9769, 13781, 17231, 32059, 32611, 36251, 46381, 47417, 55171, 68927, 103451, 130447, 182599, 189671, 220687, 236627, 241169, 273641, 275711, 350219, 374159, 413951, 471769, 497579, 498439, 520631, 521791, 583777, 601061, 635809, 647401 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS n, 4*n+3, 16*n+15, 64*n+63, 256*n+255 and 1024*n+1023 are primes. - Vincenzo Librandi, Aug 05 2010 LINKS Paul Tek, Table of n, a(n) for n = 1..10000 MATHEMATICA it5Q[n_]:=AllTrue[NestList[4#+3&, n, 5], PrimeQ]; Select[Prime[ Range[ 60000]], it5Q] (* The program uses the AllTrue function from Mathematica version 10 *) (* Harvey P. Dale, Jul 05 2015 *) PROG (MAGMA) [n: n in [1..10000000] | IsPrime(n) and IsPrime(4*n+3) and IsPrime(16*n+15) and IsPrime(64*n+63) and IsPrime(256*n+255) and IsPrime(1024*n+1023)] // Vincenzo Librandi, Aug 05 2010 CROSSREFS Sequence in context: A242878 A247696 A010092 * A145209 A035911 A069333 Adjacent sequences:  A023336 A023337 A023338 * A023340 A023341 A023342 KEYWORD nonn AUTHOR STATUS approved

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Last modified December 12 01:57 EST 2019. Contains 329948 sequences. (Running on oeis4.)