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 A083092 Numbers n such that 7*5^n + 2 is a prime. 0
 1, 3, 29, 203, 297, 617, 1211, 2969, 3037, 6489, 28029, 32229, 63927 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Values corresponding to 29, 203, 297, 617 and 1211 (848 digits) have been certified prime with Primo. Values for 2969 (2077 digits) and 3037 (2124 digits) are probable primes. There are no other terms <= 4000. a(14) > 10^5. - Tyler NeSmith LINKS Table of n, a(n) for n=1..13. EXAMPLE 37, 877, 1303851604461669921877 are 7*5^1 + 2, 7*5^3 + 2 and 7*5^29 + 2. 7*5^203 + 2 has 143 digits. PROG (PARI) for(n=1, 4000, if(isprime(7*5^n+2), print1(n, ", "))) CROSSREFS Sequence in context: A227694 A118584 A126185 * A174419 A220548 A153825 Adjacent sequences: A083089 A083090 A083091 * A083093 A083094 A083095 KEYWORD nonn AUTHOR Rick L. Shepherd, Apr 23 2003 EXTENSIONS a(10)-a(13) from Tyler NeSmith, Dec 14 2020 STATUS approved

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Last modified August 2 19:53 EDT 2024. Contains 374875 sequences. (Running on oeis4.)