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A279536
Count the squarefree numbers appearing in each interval [p,q] where (p,q) is a Goldbach partition of 2n such that all primes from p to q (inclusive) appear as a part in some Goldbach partition of p+q = 2n, and then add the results.
3
0, 0, 1, 2, 5, 3, 1, 0, 9, 0, 1, 19, 1, 0, 21, 0, 1, 10, 1, 0, 4, 0, 1, 0, 0, 3, 0, 0, 1, 68, 1, 0, 0, 5, 0, 0, 1, 0, 4, 0, 1, 25, 1, 0, 3, 0, 1, 0, 0, 3, 0, 0, 8, 0, 0, 5, 0, 0, 1, 12, 1, 0, 0, 5, 0, 0, 1, 0, 4, 0, 1, 2, 1, 0, 0, 5, 0, 0, 1, 0, 14, 0, 1, 0, 0, 5, 0, 0, 1, 0
OFFSET
1,4
COMMENTS
a(n) >= A279315(n). - Wesley Ivan Hurt, Dec 17 2016
FORMULA
a(n) = Sum_{i=3..n} (A010051(i) * A010051(2n-i) * (Sum_{j=i..2n-i} mu(j)^2) * (Product_{k=i..n} (1-abs(A010051(k)-A010051(2n-k))))), where mu is the Möbius function (A008683).
MAPLE
with(numtheory): A279536:=n->add( (pi(i)-pi(i-1)) * (pi(2*n-i)-pi(2*n-i-1)) * add(mobius(j)^2, j=i..2*n-i) * (product(1-abs((pi(k)-pi(k-1))-(pi(2*n-k)-pi(2*n-k-1))), k=i..n)), i=3..n): seq(A279536(n), n=1..100);
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Wesley Ivan Hurt, Dec 14 2016
STATUS
approved