A132105 Number of distinct Tsuro tiles which are n-gonal in shape and have 2 points per side.

1, 1, 3, 7, 30, 137, 1065, 10307, 130040, 1927853, 32809979, 625303343, 13178378742, 304081128617, 7623562484349, 206343110670031, 5996839161108904, 186254714746749377, 6156752738537004317, 215810382975655205399, 7995774673152799224930

Offset

0,3

Comments

Turning over is allowed.

See A132100 for definition and comments.

Links

Table of n, a(n) for n=0..20.

Maple

# B(n, m) gives the number of n-sided tiles with m points per side, allowing reflections (cf. comments and formula of A132100)
with(numtheory): a:=(p, r)->piecewise(p mod 2 = 1, p^(r/2)*doublefactorial(r-1), sum(p^j*binomial(r, 2*j)*doublefactorial(2*j - 1), j = 0 .. floor(r/2)));
B := (n, m)->piecewise(n*m mod 2=1, 0, add(phi(p)*a(p, m*n/p), p in divisors(n))/(2*n)+
piecewise(m mod 2=0, a(2, m*n/2)*2, a(2, m*n/2)+a(2, m*n/2-1))/4);
A132105 := n -> B(n, 2); [seq(A132105(n), n=1..20)]; # Laurent Tournier, Jul 09 2014

Crossrefs

Cf. A132100-A132104, A007769, A001147, A054499.

Sequence in context: A277739 A098644 A182322 * A019021 A110505 A354518

Adjacent sequences: A132102 A132103 A132104 * A132106 A132107 A132108

Keyword

nonn

Author

Keith F. Lynch, Oct 31 2007

Extensions

More terms from Laurent Tournier, Jul 09 2014

Status

approved