Erik Pelttari - cp's OEIS frontend

User: Erik Pelttari

Erik Pelttari has authored 2 sequences.

A262931 Numbers k such that 6 is a square mod k.

1, 2, 3, 5, 6, 10, 15, 19, 23, 25, 29, 30, 38, 43, 46, 47, 50, 53, 57, 58, 67, 69, 71, 73, 75, 86, 87, 94, 95, 97, 101, 106, 114, 115, 125, 129, 134, 138, 139, 141, 142, 145, 146, 149, 150, 159, 163, 167, 173, 174, 190, 191, 193, 194, 197, 201, 202, 211, 213

Offset: 1

Erik Pelttari, Oct 04 2015

			6^2 == 6 (mod 15), so 15 is a term.

Alois P. Heinz, Table of n, a(n) for n = 1..20000

Cf. A057125, A057126, A057762, A262932.

[n: n in [1..300] | exists(t){x : x in ResidueClassRing(n) | x^2 eq 6}]; // Vincenzo Librandi, Oct 05 2015

with(numtheory):
a:= proc(n) option remember; local k;
      for k from 1+`if`(n=1, 0, a(n-1))
      while mroot(6, 2, k)=FAIL do od; k
    end:
seq(a(n), n=1..80);  # Alois P. Heinz, Feb 24 2017

Join[{1}, Table[If[Reduce[x^2 == 6, Modulus->n] === False, Null, n], {n, 2, 300}]//Union] (* Vincenzo Librandi, Oct 05 2015 *)

for(n=1, 300, if (issquare(Mod(6, n)), print1(n", "))); \\ Altug Alkan, Oct 04 2015

A262932 Numbers k such that 7 is a square mod k.

Original entry on oeis.org

1, 2, 3, 6, 7, 9, 14, 18, 19, 21, 27, 29, 31, 37, 38, 42, 47, 53, 54, 57, 58, 59, 62, 63, 74, 81, 83, 87, 93, 94, 103, 106, 109, 111, 113, 114, 118, 126, 131, 133, 137, 139, 141, 149, 159, 162, 166, 167, 171, 174, 177, 186, 189, 193, 197, 199, 203, 206, 217, 218, 222

Offset: 1

Erik Pelttari, Oct 04 2015

			7^2 == 7 (mod 14), so 14 is a term.
5^2 == 7 (mod 18) and 13^2 == 7 (mod 18), so 18 is a term.

Alois P. Heinz, Table of n, a(n) for n = 1..20000

Cf. A057125, A057126, A057762, A262931.

[n: n in [1..300] | exists(t){x : x in ResidueClassRing(n) | x^2 eq 7}]; // Vincenzo Librandi, Oct 05 2015

with(numtheory):
a:= proc(n) option remember; local k;
      for k from 1+`if`(n=1, 0, a(n-1))
      while mroot(7, 2, k)=FAIL do od; k
    end:
seq(a(n), n=1..80);  # Alois P. Heinz, Feb 24 2017

Join[{1}, Table[If[Reduce[x^2 == 7, Modulus->n] === False, Null, n], {n, 2, 300}]//Union] (* Vincenzo Librandi, Oct 05 2015 *)

for(n=1, 300, if (issquare(Mod(7, n)), print1(n", "))); \\ Altug Alkan, Oct 04 2015

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User: Erik Pelttari

A262931 Numbers k such that 6 is a square mod k.

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