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 A261455 Numbers n such that 1+131*10^(n-1)+100^n is prime. 0
 2, 4, 13, 30, 73, 82, 120, 168, 227, 422, 433, 451, 607, 612, 798, 1527, 6958 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS No other terms < 10000. LINKS Table of n, a(n) for n=1..17. EXAMPLE For n=2, 11311 is prime. For n=3, 1013101 is not prime. For n=4, 100131001 is prime. PROG (PARI) isok(n)=isprime(1+131*10^(n-1)+100^n) \\ Anders Hellström, Aug 20 2015 CROSSREFS Cf. A171411, A171376. Sequence in context: A153933 A128601 A034500 * A077325 A148213 A148214 Adjacent sequences: A261452 A261453 A261454 * A261456 A261457 A261458 KEYWORD nonn,more AUTHOR Chai Wah Wu, Aug 20 2015 STATUS approved

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Last modified June 4 01:00 EDT 2023. Contains 363118 sequences. (Running on oeis4.)