A369247 Number of representations of 3*A057588(n) as a sum (p*q + p*r + q*r) with three odd primes p <= q <= r, where A057588 is Kummer numbers, one less than primorials.

0, 0, 1, 3, 2, 6, 10, 12, 50, 178, 150

Offset

1,4

Links

Table of n, a(n) for n=1..11.

Formula

a(n) = A369054(3*(A002110(n)-1)).

Prog

(PARI)
\\ Needs also program from A369054:
A002110(n) = prod(i=1, n, prime(i));
A369247(n) = A369054(3*(A002110(n)-1));

Crossrefs

Cf. A002110, A057588, A369054.

Sequence in context: A210756 A210748 A331889 * A367544 A340612 A362373

Adjacent sequences: A369244 A369245 A369246 * A369248 A369249 A369250

Keyword

nonn,hard,more

Author

Antti Karttunen, Jan 22 2024

Status

approved