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A223957 Number of nX4 0..3 arrays with antidiagonals unimodal and rows and diagonals nondecreasing.

%I A223957 #6 Jul 23 2025 04:41:29
%S A223957 35,805,12311,176893,2575955,37844037,559416917,8299429418,
%T A223957 123370738379,1835707326614,27327510542054,406907786331737,
%U A223957 6059551623581467,90242115362238750,1343972755503334184,20016039213440972353
%N A223957 Number of nX4 0..3 arrays with antidiagonals unimodal and rows and diagonals nondecreasing.
%C A223957 Column 4 of A223961
%H A223957 R. H. Hardin, <a href="/A223957/b223957.txt">Table of n, a(n) for n = 1..210</a>
%F A223957 Empirical: a(n) = 35*a(n-1) -411*a(n-2) +1521*a(n-3) +4495*a(n-4) -33893*a(n-5) -76333*a(n-6) +769422*a(n-7) -657978*a(n-8) -4892638*a(n-9) +11892141*a(n-10) +26545075*a(n-11) -212154687*a(n-12) +180127811*a(n-13) +844199306*a(n-14) -1964869675*a(n-15) -925267902*a(n-16) +18361374116*a(n-17) -28421809002*a(n-18) +14606204778*a(n-19) +43447425250*a(n-20) +45550238994*a(n-21) -206541843216*a(n-22) +420735920152*a(n-23) +123206624124*a(n-24) -263534650788*a(n-25) -263768865528*a(n-26) +1543560996888*a(n-27) +154734998544*a(n-28) -494508716208*a(n-29) -124707094560*a(n-30) +893424774528*a(n-31) +244581703200*a(n-32) +20427292800*a(n-33) +536699520*a(n-34) for n>36
%e A223957 Some solutions for n=3
%e A223957 ..0..0..0..2....0..2..2..2....1..2..2..3....0..0..1..1....0..0..1..3
%e A223957 ..0..0..1..3....0..1..2..3....0..2..2..3....1..1..3..3....0..1..1..3
%e A223957 ..0..1..2..3....0..3..3..3....0..2..2..3....0..3..3..3....0..1..3..3
%K A223957 nonn
%O A223957 1,1
%A A223957 _R. H. Hardin_ Mar 29 2013