Number of representations of 2^n - 1 as a sum (p*q + p*r + q*r) with three odd primes p <= q <= r.

Terms

a(0) =0a(1) =0a(2) =0a(3) =0a(4) =0a(5) =0a(6) =0a(7) =0a(8) =2a(9) =1a(10) =1a(11) =0a(12) =2a(13) =1a(14) =3a(15) =0a(16) =2a(17) =2a(18) =6a(19) =0a(20) =13a(21) =1a(22) =13a(23) =0a(24) =15a(25) =0a(26) =24a(27) =1a(28) =49a(29) =4