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 A025027 Numbers whose least quadratic nonresidue (A020649) is 19. 10
 5711, 9239, 10391, 10799, 11422, 14951, 18478, 20782, 21598, 29902, 33049, 34319, 36599, 37489, 40031, 42719, 44641, 49009, 49921, 51769, 53089, 55441, 57119, 59929, 61151, 61871, 63361, 66098, 67369, 67679, 68638, 69001, 71569, 73198, 74978, 75479 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Amiram Eldar, Table of n, a(n) for n = 1..10000 Eric Weisstein's World of Mathematics, Quadratic Nonresidue. MATHEMATICA Select[Range[20000], Min @ Complement[Range[# - 1], Mod[Range[#/2]^2, #]] == 19 &] (* Amiram Eldar, Oct 31 2020 *) PROG (PARI) residue(n, m)=local(r); r=0; for(i=1, floor(m/2), if(i^2%m==n, r=1)); r isA025027(n)=local(a); a=1; forprime(p=2, 17, a=a && residue(p, n)); a=a && !residue(19, n); a \\ Michael B. Porter, Apr 30 2010 (PARI) is(n)=forprime(p=2, 19, if(!issquare(Mod(p, n)), return(p==19))); 0 \\ Charles R Greathouse IV, Jan 24 2020 CROSSREFS Cf. A020649, A025020, A025021, A025022, A025023, A025024, A025025, A025026, A025028, A025029. Sequence in context: A235207 A252342 A237743 * A030469 A244163 A253423 Adjacent sequences:  A025024 A025025 A025026 * A025028 A025029 A025030 KEYWORD nonn AUTHOR STATUS approved

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Last modified May 5 19:31 EDT 2021. Contains 343573 sequences. (Running on oeis4.)