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A194950
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Column 0 of triangle A194949 = shifted row sums of triangle A194949.
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1
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1, 1, 2, 6, 20, 72, 260, 996, 3772, 14852, 58204, 234236, 934180, 3825428, 15493292, 64009212, 263052756, 1096235844, 4537607788, 19075092364, 79566093524, 336047432420, 1412387294716, 5993817852300, 25302001904628, 107911381154004, 457634804571804
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OFFSET
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0,3
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LINKS
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PROG
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(PARI) {a(n)=local(M=matrix(n+1, n+1, r, c, if(r>=c, 1))); for(i=1, n, M=matrix(n+1, n+1, r, c, if(r>=c, if(c==1, if(r==1, 1, sum(j=1, r-1, (M*M~)[r-j, j])), (M*M~)[r-c+1, c])))); M[n+1, 1]}
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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