A073976 Number of strings of length n over Z_6 with trace 0 and subtrace 5.

0, 2, 18, 72, 300, 1440, 7056, 39312, 252720, 1658880, 10349856, 62099136, 367960320, 2179768320, 12976433280, 77787495936, 468419708160, 2821539889152, 16960580969472, 101753146100736, 609923828966400, 3656096522698752, 21926115464435712, 131556692786614272

Offset

1,2

Links

Table of n, a(n) for n=1..24.

Max Alekseyev, PARI/GP scripts for miscellaneous math problems

F. Ruskey Strings over Z_6 with given trace and subtrace

Formula

a(n; t, s) = a(n-1; t, s) + a(n-1; t+5, s+5t+1) + a(n-1; t+4, s+4t+4) + a(n-1; t+3, s+3t+3) + a(n-1; t+2, s+2t+2) + a(n-1; t+1, s+t+1) where t is the trace and s is the subtrace.

Crossrefs

Cf. A073971, A073972, A073973, A073974, A073975, A073977, A073978, A073979, A073980, A073981, A073982, A073983, A073984, A073985, A073986, A073987, A073988, A073989, A073990, A073991, A073992, A073993, A073994.

Sequence in context: A316904 A196812 A163102 * A120361 A120358 A152887

Adjacent sequences: A073973 A073974 A073975 * A073977 A073978 A073979

Keyword

easy,nonn

Author

Frank Ruskey and Nate Kube, Aug 16 2002

Extensions

Terms a(11) onward from Max Alekseyev, Apr 09 2013

Status

approved