Denominator of n/((n+1)*(n+2)) = A026741/A045896.

Terms

a(0) =1a(1) =6a(2) =6a(3) =20a(4) =15a(5) =42a(6) =28a(7) =72a(8) =45a(9) =110a(10) =66a(11) =156a(12) =91a(13) =210a(14) =120a(15) =272a(16) =153a(17) =342a(18) =190a(19) =420a(20) =231a(21) =506a(22) =276a(23) =600a(24) =325a(25) =702a(26) =378a(27) =812a(28) =435a(29) =930