A051956 a(n) = smallest number > a(n-1) such that a(1)*a(2)*...*a(n) + 1 and a(1)*a(2)*...*a(n) - 1 are primes.

4, 15, 17, 19, 29, 57, 77, 285, 318, 354, 379, 405, 520, 521, 595, 625, 938, 1706, 1738, 2085, 2345, 2817, 4319, 4529, 7005, 8207, 8232, 9451, 9839, 11044, 11170, 12386, 12421, 12722, 14153, 15220, 15371