Number of increasing sequences of n integers x(1),...,x(n) with values in 1..3*n such that x(j) divides x(k) if j divides k.

A180385

Number of increasing sequences of n integers x(1),...,x(n) with values in 1..3*n such that x(j) divides x(k) if j divides k.

Terms

    a(0) =3a(1) =8a(2) =32a(3) =66a(4) =310a(5) =228a(6) =1286a(7) =1857a(8) =1679a(9) =1047a(10) =5462a(11) =5816a(12) =20548a(13) =10255a(14) =6969a(15) =6184a(16) =22842a(17) =20854a(18) =73561a(19) =110264a(20) =64726a(21) =24682a(22) =109028a(23) =152655a(24) =160537a(25) =60818a(26) =63827a(27) =62192a(28) =210722a(29) =302655

External references