Number of permutations i_0,i_1,...,i_n of 0,1,...,n with i_0 = 0 and i_n = n, and with i_0+i_1, i_1+i_2, ..., i_{n-1}+i_n, i_n+i_0 all coprime to both n-1 and n+1.

A228886

Number of permutations i_0,i_1,...,i_n of 0,1,...,n with i_0 = 0 and i_n = n, and with i_0+i_1, i_1+i_2, ..., i_{n-1}+i_n, i_n+i_0 all coprime to both n-1 and n+1.

Terms

    a(0) =1a(1) =0a(2) =1a(3) =0a(4) =1a(5) =8a(6) =3a(7) =24a(8) =78a(9) =1164a(10) =34a(11) =4021156a(12) =400a(13) =87180a(14) =2499480a(15) =7509358a(16) =1700352a(18) =1427688a(19) =212987263960a(20) =9533487948a(22) =29317847040

External references