A385348 - OEIS

A385348

Minimum number of products of the form P^2-i^2 to be used to obtain the GCD defined in A380472.

1, 3, 2, 4, 4, 6, 6, 4, 7, 16, 18, 7, 7, 14, 15, 15, 21, 9, 11, 19, 18, 24, 33, 11, 26, 13, 14, 47, 48, 17, 14, 19, 14, 54, 43, 14, 22, 34, 40, 33, 17, 39, 14, 17, 36, 54, 67, 38, 21, 26, 18, 135, 40, 19, 25, 25, 24, 79, 78, 20, 25, 25, 24, 101, 30, 25, 24, 24, 34, 24

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OFFSET

1,2

LINKS

Table of n, a(n) for n=1..70.

PROG

(PARI) f(n) = (2*n+2)!*(3/4-(-1)^n/4); \\ A380472

T(n, j) = gcd(vector(j, k, P=prime(k+n+1); prod(i=1, n, P^2-i^2)));

a(n) = my(x=f(n)); for (j=1, n^2, if (T(n, j) == x, return(j)));

CROSSREFS

Cf. A380472.

Sequence in context: A327637 A366409 A387209 * A345082 A047993 A033177