cp's OEIS Frontend

A212830 Number of 0..n arrays of length n+1 with no adjacent pair equal to its immediately preceding adjacent pair, and new values introduced in 0..n order.

%I A212830 #6 Jul 22 2025 22:58:22
%S A212830 2,5,13,44,168,717,3360,17092,93538,546873,3396379,22300885,154193327,
%T A212830 1118804486,8493592723,67288261914,554996479921,4756036642107,
%U A212830 42266543239132,388879705390976,3698606881082199,36312877059583874
%N A212830 Number of 0..n arrays of length n+1 with no adjacent pair equal to its immediately preceding adjacent pair, and new values introduced in 0..n order.
%C A212830 Subdiagonal 1 of A212829
%H A212830 R. H. Hardin, <a href="/A212830/b212830.txt">Table of n, a(n) for n = 1..60</a>
%e A212830 Some solutions for n
%e A212830 ..0....0....0....0....0....0....0....0....0....0....0....0....0....0....0....0
%e A212830 ..1....1....1....1....1....1....1....1....1....1....1....1....1....0....1....1
%e A212830 ..0....1....1....1....2....2....2....0....2....2....2....0....2....1....1....2
%e A212830 ..0....2....2....2....0....3....1....2....1....3....0....2....0....1....2....3
%e A212830 ..2....1....3....0....0....4....3....2....1....4....2....1....0....1....0....1
%e A212830 ..3....1....3....1....3....4....3....2....2....2....3....1....2....2....3....4
%e A212830 ..4....2....4....0....1....4....4....1....3....2....4....0....3....2....0....5
%e A212830 ..0....2....5....0....1....0....5....1....3....0....5....0....3....0....0....1
%K A212830 nonn
%O A212830 1,1
%A A212830 _R. H. Hardin_ May 28 2012