a(1) = 1, a(n) = a(n-1)*n if n is a prime, a(n) = a(n-1)+ n if n is composite.

Terms

a(0) =1a(1) =2a(2) =6a(3) =10a(4) =50a(5) =56a(6) =392a(7) =400a(8) =409a(9) =419a(10) =4609a(11) =4621a(12) =60073a(13) =60087a(14) =60102a(15) =60118a(16) =1022006a(17) =1022024a(18) =19418456a(19) =19418476a(20) =19418497a(21) =19418519a(22) =446625937a(23) =446625961a(24) =446625986a(25) =446626012a(26) =446626039a(27) =446626067a(28) =12952155943