A226549 Number of squares in all tilings of a 6 X n rectangle using integer-sided square tiles.
0, 6, 96, 654, 4938, 33502, 221672, 1426734, 9014839, 56128696, 345447208, 2106033948, 12739126739, 76548375758, 457375097789, 2719454021744, 16100269337597, 94961606031670, 558226473615469, 3271710478901046, 19123726111508773, 111510459865449832
Offset: 0
Links
- Alois P. Heinz, Table of n, a(n) for n = 0..1000
Formula
G.f.: (4*x^23 +60*x^22 +203*x^21 +308*x^20 -35*x^19 -660*x^18 -964*x^17 -612*x^16 +239*x^15 +344*x^14 +683*x^13 +686*x^12 +1156*x^11 +1944*x^10 -341*x^9 -2280*x^8 -1775*x^7 +588*x^6 +1550*x^5 +70*x^4 -498*x^3 -48*x^2 +60*x+6)*x / (2*x^15 +7*x^14 +12*x^13 +6*x^12 -18*x^11 -13*x^10 -8*x^9 -27*x^8 -32*x^7 +x^6 +40*x^5 +34*x^4 -3*x^3 -15*x^2 -3*x+1)^2.