A366324 Number of tilings of a 5 X n rectangle using n pentominoes of shapes T, W, Y, X.
1, 0, 0, 0, 2, 2, 8, 0, 22, 40, 134, 100, 266, 448, 1610, 2454, 4806, 7064, 19774, 38320, 81174, 128604, 277540, 553762, 1222204, 2210510, 4352240, 8339138, 17869740, 34938578, 69204722, 131277114, 267512514, 533554754, 1074570418, 2076822340, 4120024394
Offset: 0
Links
- Alois P. Heinz, Table of n, a(n) for n = 0..3367
- Wikipedia, Pentomino
- Index entries for linear recurrences with constant coefficients, signature (0, 1, 0, 5, 9, 6, -5, 5, 8, 48, -13, -37, -36, 58, 37, -37, -94, 8, 56, 188, -254, -181, 92, -55, 155, -267, -346, 91, 444, -61, 56, -258, 36, 371, 116, -122, -94, 40, 116, 64, 0, 16, 0, 32).
Formula
G.f.: (16*x^42 +32*x^41 +16*x^40 +20*x^39 +8*x^38 +4*x^37 -40*x^36 +8*x^35 +13*x^34 -42*x^33 -84*x^32 +4*x^31 -79*x^30 +82*x^29 +61*x^28 -50*x^27 -33*x^26 +47*x^25 +21*x^24 +36*x^23 -23*x^22 -102*x^21 +16*x^20 +26*x^19 +12*x^18 -14*x^17 -5*x^16 +x^15 +28*x^14 -11*x^12 +x^11 +6*x^10 -4*x^9 +x^8 -3*x^7 +7*x^5 +3*x^4 +x^2 -1) / (32*x^44 +16*x^42 +64*x^40 +116*x^39 +40*x^38 -94*x^37 -122*x^36 +116*x^35 +371*x^34 +36*x^33 -258*x^32 +56*x^31 -61*x^30 +444*x^29 +91*x^28 -346*x^27 -267*x^26 +155*x^25 -55*x^24 +92*x^23 -181*x^22 -254*x^21 +188*x^20 +56*x^19 +8*x^18 -94*x^17 -37*x^16 +37*x^15 +58*x^14 -36*x^13 -37*x^12 -13*x^11 +48*x^10 +8*x^9 +5*x^8 -5*x^7 +6*x^6 +9*x^5 +5*x^4 +x^2 -1).