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 A188698 Numbers k such that 1+k, 1+k^2, 1+k^4 and 1+k^16 are all prime. 0
 1, 2, 690, 33190, 57106, 77140, 135606, 258990, 303430, 331140, 337536, 359230, 375646, 455526, 458326, 493396, 548226, 550540, 585106, 602056, 659250, 680830, 742306, 800406, 827680, 870240, 918340, 925390, 968320, 1203100, 1273890, 1455526, 1497576, 1605016 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Subsequence of A070325, which itself is a subsequence of A070689, which itself is a subsequence of A006093. LINKS Table of n, a(n) for n=1..34. EXAMPLE a(3) = 690 = A070689(32) = A070325(11) = A006093(125). PROG (Magma) [n: n in [0..7000000]| IsPrime(1+n) and IsPrime(1+n^2) and IsPrime(1+n^4) and IsPrime(1+n^16)]; // Vincenzo Librandi, Apr 11 2011 CROSSREFS Sequence in context: A079195 A120123 A140014 * A209364 A106301 A127623 Adjacent sequences: A188695 A188696 A188697 * A188699 A188700 A188701 KEYWORD nonn AUTHOR Zak Seidov, Apr 09 2011 EXTENSIONS a(1) = 1 prepended by Vincenzo Librandi, Apr 11 2011 STATUS approved

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Last modified June 9 17:32 EDT 2023. Contains 363183 sequences. (Running on oeis4.)