A087521 Smallest prime p such that the prime signature of p+1 has not occurred earlier.

2, 3, 5, 7, 11, 23, 29, 31, 47, 59, 71, 127, 167, 179, 191, 223, 239, 359, 383, 389, 419, 431, 479, 719, 839, 863, 971, 1151, 1259, 1279, 1439, 1511, 2111, 2309, 2591, 2687, 2699, 2879, 3023, 3119, 3359, 3583, 3779, 5039, 5119, 5399, 6047, 6143, 6299, 6719