|
|
A125618
|
|
(Sum of the squares of the quadratic nonresidues of prime(n)) / prime(n).
|
|
6
|
|
|
10, 23, 23, 40, 65, 117, 127, 199, 209, 254, 319, 474, 441, 654, 583, 765, 1071, 826, 1218, 1252, 1246, 1476, 1637, 2000, 2042, 1899, 2028, 2974, 3155, 2998, 3394, 3593, 4291, 3983, 4469, 5525, 4867, 5743, 5301, 7274, 5964, 6321, 7446, 7684, 9013, 9099
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
4,1
|
|
COMMENTS
|
Always an integer for primes > 5.
|
|
REFERENCES
|
D. M. Burton, Elementary Number Theory, McGraw-Hill, Sixth Edition (2007), p. 185.
|
|
LINKS
|
|
|
FORMULA
|
|
|
EXAMPLE
|
The quadratic nonresidues of 7=prime(4) are 3, 5 and 6. Hence a(4) = (3^2 + 5^2 + 6^2)/7 = 10.
|
|
PROG
|
(PARI) vector(46, m, p=prime(m+3); t=1; for(i=2, (p-1)/2, t+=((i^2)%p)^2); (p-1)*(2*p-1)/6-t/p)
|
|
CROSSREFS
|
|
|
KEYWORD
|
easy,nonn
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|