Consider the group freely generated by an element U of order 3 and an element S of order 2. a(n) gives the number of words in the alphabet {U,S} of length n that are equal to unity.
A265434
Consider the group freely generated by an element U of order 3 and an element S of order 2. a(n) gives the number of words in the alphabet {U,S} of length n that are equal to unity.
Terms
- a(0) =1a(1) =0a(2) =1a(3) =1a(4) =1a(5) =5a(6) =2a(7) =14a(8) =13a(9) =31a(10) =66a(11) =77a(12) =240a(13) =286a(14) =722a(15) =1226a(16) =2141a(17) =4760a(18) =7268a(19) =16473a(20) =27716a(21) =54615a(22) =106217a(23) =187818a(24) =388084a(25) =685830a(26) =1370162a(27) =2569351a(28) =4849538a(29) =9526355
External references
- oeis: A265434