Semiprimes (A001358) that are sums of distinct factorials.

Terms

a(0) =6a(1) =9a(2) =25a(3) =26a(4) =33a(5) =121a(6) =122a(7) =123a(8) =129a(9) =145a(10) =146a(11) =721a(12) =723a(13) =745a(14) =746a(15) =753a(16) =841a(17) =842a(18) =843a(19) =849a(20) =865a(21) =866a(22) =871a(23) =5041a(24) =5042a(25) =5065a(26) =5071a(27) =5161a(28) =5163a(29) =5169