O.g.f.: exp( Sum_{n>=1} (sigma(2*n)-sigma(n))^3 * x^n/n ).
A193539
O.g.f.: exp( Sum_{n>=1} (sigma(2*n)-sigma(n))^3 * x^n/n ).
Terms
- a(0) =1a(1) =8a(2) =64a(3) =512a(4) =3200a(5) =19392a(6) =112128a(7) =598016a(8) =3088896a(9) =15362408a(10) =73331264a(11) =340653056a(12) =1538392064a(13) =6762336448a(14) =29072665600a(15) =122299068416a(16) =504128374784
External references
- oeis: A193539