A057129 -4 is a square mod n.

1, 2, 4, 5, 8, 10, 13, 17, 20, 25, 26, 29, 34, 37, 40, 41, 50, 52, 53, 58, 61, 65, 68, 73, 74, 82, 85, 89, 97, 100, 101, 104, 106, 109, 113, 116, 122, 125, 130, 136, 137, 145, 146, 148, 149, 157, 164, 169, 170, 173, 178, 181, 185, 193, 194, 197, 200, 202, 205, 212

Offset

1,2

Comments

Numbers that are not multiples of 16 and for which all odd prime factors are congruent to 1 mod 4. - Eric M. Schmidt, Apr 21 2013

Links

Eric M. Schmidt, Table of n, a(n) for n = 1..1000

Prog

(Sage)
def A057129(n) :
    if n%16==0: return False
    for (p, m) in factor(n) :
        if p % 4 not in [1, 2] : return False
    return True
# Eric M. Schmidt, Apr 21 2013

Crossrefs

Includes the primes in A002313 and these (primes congruent to {1, 2} mod 4) are the prime factors of the terms in this sequence. Cf. A008784, A057125, A057126, A057127, A057128.

Sequence in context: A191985 A126026 A199425 * A281898 A036404 A347355

Adjacent sequences: A057126 A057127 A057128 * A057130 A057131 A057132

Keyword

nonn

Author

Henry Bottomley, Aug 10 2000

Status

approved