a(1)=3; thereafter, if n odd, a(n) = a(n-1)-st prime, and if n even, a(n) = a(n-1)-st nonprime.

A280029

a(1)=3; thereafter, if n odd, a(n) = a(n-1)-st prime, and if n even, a(n) = a(n-1)-st nonprime.

Terms

    a(0) =3a(1) =6a(2) =13a(3) =21a(4) =73a(5) =98a(6) =521a(7) =636a(8) =4721a(9) =5439a(10) =53323a(11) =59318a(12) =737183a(13) =801235a(14) =12215237a(15) =13068626a(16) =238205651a(17) =251987681a(18) =5381022817a(19) =5644769560a(20) =138933578143a(21) =144807081479

External references