login
A373224
Row sums of A373223.
4
0, 1, 2, 1, 0, 5, 6, 1, 0, 9, 0, 11, 12, 1, 0, 15, 0, 17, 0, -1, 20, -1, -2, 23, 24, 25, 0, -1, 28, 29, 0, -1, 32, -1, 34, -1, 36, -1, -2, 39, -2, 41, -2, 43, 44, -1, -2, -3, -4, 49, 50, -3, 52, -3, 54, -3, 56, -3, 58, 59, -2, 61, -2, -3, 64, 65, -2, 67, -2, 69, 70, -1, -2
OFFSET
1,3
FORMULA
a(k) = k - 1 <==> k = 1 or 2 or k term of A080147. In other words: If we index the primes starting at 0 then 0, 1 and the indices of the Pythagorean primes (A002144) are the fixed points of this map.
MAPLE
A373224 := n -> local k; add(A373223(n, k), k = 1..n):
lprint(seq(A373224(n), n = 1..73));
PROG
(PARI) KP(p, q) = kronecker(p, q);
T(n, k) = my(p=prime(n), q=prime(k)); KP(p, q) * KP(q, p);
a(n) = vecsum(vector(n, k, T(n, k))); \\ Michel Marcus, May 30 2024
CROSSREFS
KEYWORD
sign
AUTHOR
Peter Luschny, May 28 2024
STATUS
approved