a(1) = 1, then add, multiply, subtract, multiply 2, 3, 4, 5; 6, 7, 8, 9; ... in that order.

A077384

a(1) = 1, then add, multiply, subtract, multiply 2, 3, 4, 5; 6, 7, 8, 9; ... in that order.

Terms

    a(0) =1a(1) =3a(2) =9a(3) =5a(4) =25a(5) =31a(6) =217a(7) =209a(8) =1881a(9) =1891a(10) =20801a(11) =20789a(12) =270257a(13) =270271a(14) =4054065a(15) =4054049a(16) =68918833a(17) =68918851a(18) =1309458169a(19) =1309458149a(20) =27498621129a(21) =27498621151a(22) =632468286473a(23) =632468286449

External references