a(n) = 1 + (n-1) + (n-1)*[n/2-1] + (n-1)*[n/2-1]*[n/3-1] + (n-1)*[n/2-1]*[n/3-1]*[n/4-1] +... for n>0 with a(0)=1, where [x] = floor(x).

A207643

a(n) = 1 + (n-1) + (n-1)*[n/2-1] + (n-1)*[n/2-1]*[n/3-1] + (n-1)*[n/2-1]*[n/3-1]*[n/4-1] +... for n>0 with a(0)=1, where [x] = floor(x).

Terms

    a(0) =1a(1) =1a(2) =2a(3) =3a(4) =7a(5) =9a(6) =26a(7) =31a(8) =71a(9) =129a(10) =262a(11) =291a(12) =1222a(13) =1333a(14) =2198a(15) =5139a(16) =11881a(17) =12673a(18) =39594a(19) =41923a(20) =117326a(21) =251841a(22) =354292a(23) =371163a(24) =1870453a(25) =2598577a(26) =3456926a(27) =7103955a(28) =16665859a(29) =17283113

External references