a(n) = Sum_{k=1..10^n} tau_4(k), where tau_4 is the number of ordered factorizations into 4 factors (A007426).
A189020
a(n) = Sum_{k=1..10^n} tau_4(k), where tau_4 is the number of ordered factorizations into 4 factors (A007426).
Terms
- a(0) =1a(1) =89a(2) =3575a(3) =93237a(4) =1951526a(5) =35270969a(6) =578262093a(7) =8840109380a(8) =128217432396
External references
- oeis: A189020