%I A135882
%S A135882 1,2,7,34,215,1698,16220,182714,2378780,35219202,585245185,10797322816,
%T A135882 219163958124,4856832298391,116735215192864,3025759884533190,
%U A135882 84155831914971391,2500599947944218716,79072271422935678302
%N A135882 Column 1 of triangle A135880.
%H A135882 Paul D. Hanna, <a href="b135882.txt">Table of n, a(n) for n = 0..79</
a>
%e A135882 Equals column 1 of triangle P=A135880:
%e A135882 1;
%e A135882 1, 1;
%e A135882 2, 2, 1;
%e A135882 6, 7, 3, 1;
%e A135882 25, 34, 15, 4, 1;
%e A135882 138, 215, 99, 26, 5, 1;
%e A135882 970, 1698, 814, 216, 40, 6, 1; ...
%e A135882 where column k of P^2 equals column 0 of P^(2k+2)
%e A135882 such that column 0 of P^2 equals column 0 of P shift left.
%o A135882 (PARI) {a(n)=local(P=Mat(1),R,PShR);if(n==0,1,for(i=0,n, PShR=matrix(#P,
#P, r,c, if(r>=c,if(r==c,1,if(c==1,0,P[r-1,c-1]))));R=P*PShR; R=matrix(#P+1,
#P+1, r,c, if(r>=c, if(r<#P+1,R[r,c], if(c==1,(P^2)[ #P,1],(P^(2*c-1))[r-c+1,
1])))); P=matrix(#R, #R, r,c, if(r>=c, if(r<#R,P[r,c], (R^c)[r-c+1,
1]))));P[n+2,2])}
%Y A135882 Cf. A135880; other columns: A135881, A135883, A135884.
%Y A135882 Sequence in context: A002720 A111539 A074059 this_sequence A143740 A049463
A029894
%Y A135882 Adjacent sequences: A135879 A135880 A135881 this_sequence A135883 A135884
A135885
%K A135882 nonn
%O A135882 0,2
%A A135882 Paul D. Hanna (pauldhanna(AT)juno.com), Dec 15 2007
%E A135882 Error in entries (false comma) corrected by N. J. A. Sloane (njas(AT)research.att.com),
Jan 23 2008
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