Number of n-node trees with a forbidden limb of length 5.

Terms

a(0) =1a(1) =1a(2) =1a(3) =1a(4) =2a(5) =3a(6) =5a(7) =10a(8) =21a(9) =43a(10) =97a(11) =215a(12) =503a(13) =1187a(14) =2876a(15) =7033a(16) =17510a(17) =43961a(18) =111664a(19) =285809a(20) =737632a(21) =1915993a(22) =5008652a(23) =13163785a(24) =34774873a(25) =92282214a(26) =245930746a(27) =657931603a(28) =1766481135a(29) =4758553683