Least integer k >= 0 such that binomial(k*n,k+1) = -1 mod n, or -1 if no such integer exists.

Terms

a(0) =0a(1) =1a(2) =2a(3) =3a(4) =4a(5) =341a(6) =6a(7) =79a(8) =8a(9) =19599a(10) =10a(11) =3937027727a(12) =12a(13) =2841a(14) =22679a(15) =47a(16) =16a(17) =18459448019a(18) =18a(19) =179a(20) =146a(21) =4003647a(22) =22a(23) =77934182399a(24) =24a(25) =299519a(26) =80a(27) =29952579a(28) =28