Half the number of 0..3 arrays of length n+2 with second differences nonzero.

A212777

Half the number of 0..3 arrays of length n+2 with second differences nonzero.

Terms

    a(0) =28a(1) =99a(2) =350a(3) =1238a(4) =4379a(5) =15490a(6) =54793a(7) =193821a(8) =685609a(9) =2425226a(10) =8578828a(11) =30346157a(12) =107344412a(13) =379712753a(14) =1343169821a(15) =4751236703a(16) =16806698494a(17) =59450861306a(18) =210297394895a(19) =743891565706

External references