Number of compositions [p(1), p(2), ..., p(k)] of n such that p(j) - p(j-1) <= 2.

Terms

a(0) =1a(1) =1a(2) =2a(3) =4a(4) =8a(5) =15a(6) =29a(7) =55a(8) =105a(9) =199a(10) =378a(11) =716a(12) =1358a(13) =2572a(14) =4873a(15) =9229a(16) =17480a(17) =33102a(18) =62688a(19) =118709a(20) =224795a(21) =425676a(22) =806068a(23) =1526371a(24) =2890338a(25) =5473125a(26) =10363871a(27) =19624925a(28) =37161558a(29) =70368705