The number of length n sequences on {0,1,2}(ternary sequences) that contain a prime number of 2's.

A178851

The number of length n sequences on {0,1,2}(ternary sequences) that contain a prime number of 2's.

Terms

    a(0) =0a(1) =0a(2) =1a(3) =7a(4) =32a(5) =121a(6) =412a(7) =1317a(8) =4048a(9) =12144a(10) =35904a(11) =105249a(12) =306968a(13) =892217a(14) =2585468a(15) =7468532a(16) =21500800a(17) =61688513a(18) =176477988a(19) =503906221a(20) =1438235592a(21) =4110846808a(22) =11789919200a(23) =33991337521a(24) =98657320240a(25) =288505634480a(26) =850146795840

External references