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 A101996 Primes of the form 8*k-1 such that 4*k-1, 16*k-1, 32*k-1 and 64*k-1 are also primes. 8
 359, 107279, 126839, 253679, 254279, 508559, 592199, 681839, 1214639, 1621079, 2138399, 2245319, 3197399, 3243239, 3641999, 3732479, 3825359, 3841919, 4090679, 4276799, 4315799, 4490639, 4556159, 4714439, 5335559, 5731679 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Amiram Eldar, Table of n, a(n) for n = 1..10000 (terms 1..750 from Harvey P. Dale) FORMULA a(n) = 8*A101994(n) - 1 = 2*A101995(n) + 1. - Amiram Eldar, May 13 2024 EXAMPLE 4*45-1 = 179, 8*45-1 = 359, 16*45-1 = 719, 32*45-1 = 1439 and 64*45-1 = 2879 are primes, so 359 is a term. MATHEMATICA 8#-1&/@Select[Range[720000], AllTrue[{4, 8, 16, 32, 64}#-1, PrimeQ]&] (* Harvey P. Dale, Jan 17 2023 *) Select[Table[2^Range[2, 6] n-1, {n, 750000}], AllTrue[#, PrimeQ]&][[;; , 2]] (* Harvey P. Dale, Jun 03 2023 *) PROG (PARI) is(k) = if(k % 8 == 7, my(m = k\8 + 1); isprime(4*m-1) && isprime(8*m-1) && isprime(16*m-1) && isprime(32*m-1) && isprime(64*m-1), 0); \\ Amiram Eldar, May 13 2024 CROSSREFS Cf. A101789, A101994, A101995, A101997, A101998, A101999. Subsequence of A007522, A101792 and A101796. Sequence in context: A013325 A344284 A179678 * A237017 A360943 A097570 Adjacent sequences: A101993 A101994 A101995 * A101997 A101998 A101999 KEYWORD easy,nonn AUTHOR Douglas Stones (dssto1(AT)student.monash.edu.au), Dec 23 2004 EXTENSIONS Corrected by T. D. Noe, Nov 15 2006 STATUS approved

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Last modified September 12 11:37 EDT 2024. Contains 375851 sequences. (Running on oeis4.)