A302633 Number of nX6 0..1 arrays with every element equal to 0, 1, 3 or 6 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.
13, 65, 47, 149, 691, 2262, 8981, 35772, 135125, 522265, 2030558, 7817366, 30184397, 116738915, 450741840, 1740832183, 6725944705, 25979920451, 100351084472, 387650634193, 1497420252119, 5784201010250, 22343397443993, 86308461484188
Offset: 1
Keywords
Examples
Some solutions for n=5 ..0..1..0..1..0..1. .0..1..0..1..0..1. .0..1..1..0..0..1. .0..1..0..1..0..1 ..0..1..0..1..0..0. .0..1..0..1..0..0. .1..0..1..0..1..0. .0..0..0..1..0..1 ..0..1..1..1..0..1. .0..1..0..1..0..1. .1..0..1..0..1..0. .0..1..0..1..0..0 ..0..1..0..1..0..1. .0..1..0..1..1..1. .1..1..1..0..0..0. .0..1..0..1..0..1 ..0..1..0..1..0..1. .0..1..0..1..0..1. .1..0..1..0..1..0. .0..0..1..1..0..1
Links
- R. H. Hardin, Table of n, a(n) for n = 1..210
Crossrefs
Cf. A302635.
Formula
Empirical: a(n) = 4*a(n-2) +39*a(n-3) +50*a(n-4) -2*a(n-5) -393*a(n-6) -694*a(n-7) -455*a(n-8) +1693*a(n-9) +3775*a(n-10) +3444*a(n-11) -2775*a(n-12) -9804*a(n-13) -11520*a(n-14) -2477*a(n-15) +11606*a(n-16) +20666*a(n-17) +16150*a(n-18) -984*a(n-19) -19093*a(n-20) -24794*a(n-21) -14731*a(n-22) +3238*a(n-23) +15647*a(n-24) +18561*a(n-25) +12040*a(n-26) +2792*a(n-27) -5734*a(n-28) -9936*a(n-29) -10264*a(n-30) -7542*a(n-31) -2505*a(n-32) +3231*a(n-33) +6835*a(n-34) +6669*a(n-35) +3407*a(n-36) -82*a(n-37) -2685*a(n-38) -3140*a(n-39) -2156*a(n-40) -311*a(n-41) +848*a(n-42) +1060*a(n-43) +623*a(n-44) +130*a(n-45) -148*a(n-46) -209*a(n-47) -116*a(n-48) -18*a(n-49) +34*a(n-50) +24*a(n-51) +6*a(n-52) -2*a(n-53) -a(n-54) for n>65.
Comments