Eigensequence of A047999, Sierpinski's gasket.

Terms

a(0) =1a(1) =2a(2) =3a(3) =7a(4) =8a(5) =17a(6) =27a(7) =66a(8) =67a(9) =135a(10) =204a(11) =479a(12) =553a(13) =1182a(14) =1889a(15) =4641a(16) =4642a(17) =9285a(18) =13929a(19) =32504a(20) =37153a(21) =78957a(22) =125414a(23) =306591a(24) =311299a(25) =627308a(26) =948029a(27) =2226203a(28) =2570492a(29) =5494707