Squarefree numbers (A005117) of the form p*q*r with prime factors p, q, r with q = 2*p-1 and r = 2*q-1.
A231815
Squarefree numbers (A005117) of the form p*q*r with prime factors p, q, r with q = 2*p-1 and r = 2*q-1.
Terms
- a(0) =30a(1) =51319a(2) =3882139a(3) =289022911a(4) =674910259a(5) =991523479a(6) =1893583519a(7) =4550912389a(8) =9761467669a(9) =16721570539a(10) =28685399311a(11) =72886214809a(12) =77372307511a(13) =82720376839a(14) =98685849571a(15) =173850108931a(16) =220038912319a(17) =229352039821a(18) =240313142749a(19) =257401051861a(20) =428178002569
External references
- oeis: A231815