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A132785
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Main diagonal of triangle A132784.
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2
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1, 1, 1, 1, 2, 7, 40, 342, 4118, 66581, 1393998, 36722251, 1189340060, 46466456210, 2155486553918, 117137645018204, 7372271485024724, 532031521606758006, 43644205623323138712, 4038679603699275061593, 418716209086799704826908
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OFFSET
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0,5
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COMMENTS
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Also equals (with offset) the row sums and rightmost border of triangle A132784.
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LINKS
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PROG
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(PARI) {a(n)=local(A=[1]); if(n==0, 1, for(i=1, n, B=Vec(Pol(A)/(1-x +x*O(x^(i*(i-1)/2)))); A=concat(vector(i), B)); A[n+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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