Differences of two factorial numbers.

Terms

a(0) =0a(1) =1a(2) =4a(3) =5a(4) =18a(5) =22a(6) =23a(7) =96a(8) =114a(9) =118a(10) =119a(11) =600a(12) =696a(13) =714a(14) =718a(15) =719a(16) =4320a(17) =4920a(18) =5016a(19) =5034a(20) =5038a(21) =5039a(22) =35280a(23) =39600a(24) =40200a(25) =40296a(26) =40314a(27) =40318a(28) =40319a(29) =322560