A245274 Composite terms in sequence {A243937(n)-1}.

35, 65, 77, 95, 119, 121, 125, 143, 155, 161, 185, 187, 203, 209, 215, 217, 221, 245, 247, 275, 287, 289, 299, 305, 323, 329, 335, 341, 365, 371, 377, 395, 407, 413, 425, 427, 437, 455, 473, 485, 497, 515, 517, 527, 529, 533, 539, 545, 551, 575, 581, 583, 605

Offset: 1

Author

Vladimir Shevelev, Jul 16 2014

Keywords

• nonn

Comments

See comment in A243937.

If prime p is not in A062326, then p^2 is in the sequence.

If p>3 and p,p+2 are twin primes, then p*(p+2) is in the sequence. Indeed, it can be shown that in this case (p+1)^2 is in A243937. lpf((p+1)^2-1)=p while lpf((p+1)^2-3)=3, since for lesser p>3 of twin prime p+1==0(mod 6).

Crossrefs

Cf. A245272, A243937, A245024.

Extensions

More terms from Peter J. C. Moses, Jul 16 2014