A Jacobsthal convolution.

Terms

a(0) =1a(1) =0a(2) =1a(3) =4a(4) =5a(5) =8a(6) =25a(7) =44a(8) =77a(9) =176a(10) =353a(11) =660a(12) =1365a(13) =2776a(14) =5417a(15) =10876a(16) =21981a(17) =43648a(18) =87153a(19) =175076a(20) =349669a(21) =698280a(22) =1398585a(23) =2797260a(24) =5590381a(25) =11184720a(26) =22373761a(27) =44735284a(28) =89474165a(29) =178969208