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 A025026 Least non-residue mod n is 17. 0
 1559, 2999, 3118, 5998, 6551, 8089, 8761, 13102, 13729, 14759, 16178, 16631, 17522, 18119, 19009, 21121, 21961, 23399, 24049, 27431, 27458, 27551, 28081, 29518, 31249, 33262, 33289, 33479, 35281, 35591, 36238, 36791, 38018, 42242, 43391, 43922, 43991 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS PROG (PARI) residue(n, m)=local(r); r=0; for(i=1, floor(m/2), if(i^2%m==n, r=1)); r isA025026(n)={local(a); a=1; forprime(p=2, 13, a=a && residue(p, n)); a=a && !residue(17, n); a \\ Michael B. Porter, Apr 30 2010 (PARI) is(n)=issquare(Mod(2, n)) && issquare(Mod(3, n)) && issquare(Mod(5, n)) && issquare(Mod(7, n)) && issquare(Mod(11, n)) && issquare(Mod(13, n)) && !issquare(Mod(17, n)) \\ Charles R Greathouse IV, Jan 24 2020 CROSSREFS Sequence in context: A252321 A252314 A186393 * A302057 A092001 A069475 Adjacent sequences:  A025023 A025024 A025025 * A025027 A025028 A025029 KEYWORD nonn AUTHOR STATUS approved

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Last modified June 6 04:15 EDT 2020. Contains 334859 sequences. (Running on oeis4.)