Number of bicolored trees on n unlabeled nodes such that black nodes are not adjacent to each other.
A339830
Number of bicolored trees on n unlabeled nodes such that black nodes are not adjacent to each other.
Terms
- a(0) =1a(1) =2a(2) =2a(3) =4a(4) =10a(5) =26a(6) =75a(7) =234a(8) =768a(9) =2647a(10) =9466a(11) =34818a(12) =131149a(13) =503640a(14) =1965552a(15) =7777081a(16) =31138051a(17) =125961762a(18) =514189976a(19) =2115922969a(20) =8769932062a(21) =36584593158a(22) =153510347137a(23) =647564907923
External references
- oeis: A339830