1,1

Some terms may overlap: e.g., k=9 and k=10 both begin with p=175229 where p+4 = 175233.

For each p, the semiprime is p+4.

a(2)=33 because if p=29, then p+4 is 33 and semiprime (3*11).

Cf. A001358 A137625 A137626 A136628.

Sequence in context: A036543 A140413 A097804 this_sequence A046997 A013488 A063423

Adjacent sequences: A137624 A137625 A137626 this_sequence A137628 A137629 A137630

easy,more,nonn

Enoch Haga (Enokh(AT)comcast.net), Jan 30 2008