cp's OEIS Frontend

A252172 Number of length n+2 0..3 arrays with the sum of the maximum minus the minimum of adjacent triples multiplied by some arrangement of +-1 equal to zero.

%I A252172 #6 Jul 23 2025 13:36:57
%S A252172 4,132,264,1872,6820,31420,123826,515268,2058802,8332796,33350162,
%T A252172 133891940,535789038,2145632584,8584207782,34349419412,137408677592,
%U A252172 549699224224,2198863697876,8795786194236,35183533311476,140735839290104
%N A252172 Number of length n+2 0..3 arrays with the sum of the maximum minus the minimum of adjacent triples multiplied by some arrangement of +-1 equal to zero.
%C A252172 Column 3 of A252177
%H A252172 R. H. Hardin, <a href="/A252172/b252172.txt">Table of n, a(n) for n = 1..129</a>
%F A252172 Empirical: a(n) = 13*a(n-1) -60*a(n-2) +76*a(n-3) +310*a(n-4) -1328*a(n-5) +1601*a(n-6) +1043*a(n-7) -4739*a(n-8) +6283*a(n-9) -16535*a(n-10) +47913*a(n-11) -56399*a(n-12) -41587*a(n-13) +227738*a(n-14) -387264*a(n-15) +541852*a(n-16) -755788*a(n-17) +635056*a(n-18) +469432*a(n-19) -2549608*a(n-20) +5018568*a(n-21) -7394016*a(n-22) +8952448*a(n-23) -8287952*a(n-24) +4052560*a(n-25) +3641808*a(n-26) -12878128*a(n-27) +21320784*a(n-28) -27162288*a(n-29) +29035680*a(n-30) -26480832*a(n-31) +20563584*a(n-32) -13528064*a(n-33) +7524864*a(n-34) -3517952*a(n-35) +1345536*a(n-36) -396288*a(n-37) +79872*a(n-38) -8192*a(n-39) for n>40
%e A252172 Some solutions for n=6
%e A252172 ..3....2....1....2....1....3....1....2....0....1....0....0....2....0....3....0
%e A252172 ..2....2....1....3....1....2....3....0....1....1....3....3....2....3....2....3
%e A252172 ..3....3....0....1....0....3....0....0....2....0....2....3....2....3....3....0
%e A252172 ..0....2....1....1....1....1....3....0....1....0....2....2....1....1....2....0
%e A252172 ..1....1....1....0....0....1....0....3....2....0....3....3....2....3....1....3
%e A252172 ..0....0....3....0....3....1....0....1....3....0....1....0....1....1....0....1
%e A252172 ..3....1....3....3....3....0....2....3....2....2....1....0....3....0....3....2
%e A252172 ..3....0....2....1....0....2....0....1....2....2....2....3....0....2....1....0
%K A252172 nonn
%O A252172 1,1
%A A252172 _R. H. Hardin_, Dec 15 2014