A265924 Number of nX4 0..4 arrays with the absolute differences of each element with its with horizontal and antidiagonal neighbors unique.

340, 9016, 72772, 542940, 4044156, 30029860, 225444912, 1691502456, 12779302796, 96726712256, 733594037948, 5585468980116, 42451575314372, 324411240385960, 2468510420444928, 18903703259295268, 143946266428000640

Offset: 1

Author

R. H. Hardin, Dec 18 2015

Keywords

• nonn

Comments

Column 4 of A265928.

Examples

			Some solutions for n=3
..0..0..4..4....4..0..1..3....4..2..1..3....1..3..3..2....0..0..1..3
..1..1..0..3....3..4..4..2....2..1..3..4....2..0..0..1....3..1..4..0
..3..0..1..4....2..1..3..3....4..0..0..1....4..4..3..0....2..4..3..1
		

Links

• R. H. Hardin, Table of n, a(n) for n = 1..210

Crossrefs

Cf. A265928.

Formula

Empirical: a(n) = 16*a(n-1) +74*a(n-2) -2388*a(n-3) +3439*a(n-4) +135306*a(n-5) -522734*a(n-6) -3439014*a(n-7) [phone]*a(n-8) [phone]*a(n-9) -333465409*a(n-10) -59196434*a(n-11) [phone]*a(n-12) [phone]*a(n-13) -9296733480*a(n-14) -4787400052*a(n-15) [phone]*a(n-16) [phone]*a(n-17) [phone]*a(n-18) -14763124864*a(n-19) -19831398480*a(n-20) -12928318048*a(n-21) -3167850512*a(n-22) [phone]*a(n-23) [phone]*a(n-24) [phone]*a(n-25) [phone]*a(n-26) +6553600*a(n-27) -65536*a(n-28) for n>32