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 A136582 Sqrt(10)-primes: primes obtained by concatenating the first digits in the decimal expansion of sqrt(10). 6
 3, 31, 3162277, 316227766016837933, 316227766016837933199889354443271 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS n such that floor(sqrt(10^(2*n-1))) is prime (1, 2, 7, 18, 33, ...) are given in A136583. This sequence is the list of prime terms in A017934. LINKS Table of n, a(n) for n=1..5. FORMULA a(n) = A017934(2*A136583(n)-1). PROG (Magma) // by Jason Kimberley, Aug 2011 for n in [1..499 by 2] do f := Isqrt(10^n); if IsPrime(f) then printf "%o, ", f; end if; end for; CROSSREFS Cf. A010467, A017934, A017934, A131581, A132153, A136583, A175733, A175734. Sequence in context: A282973 A005042 A317482 * A356516 A173649 A210648 Adjacent sequences: A136579 A136580 A136581 * A136583 A136584 A136585 KEYWORD nonn,base AUTHOR Lekraj Beedassy, Jan 09 2008 STATUS approved

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Last modified June 8 00:26 EDT 2023. Contains 363157 sequences. (Running on oeis4.)