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A187123
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Row sums of triangle A187120.
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4
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1, 4, 22, 164, 1599, 19624, 292799, 5162063, 105139954, 2430528374, 62877375426, 1799698534522, 56461862815496, 1926534563625822, 71024188655886038, 2813193432059656268, 119136308527407025379, 5371507426340905440926
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OFFSET
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3,2
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COMMENTS
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Definition of triangle: A187120(n,k) = [y^k] R_{n-1}(y+y^2) for k=3..n, n>3, where R_n(y) is the n-th row polynomial starting with R_3(y)=y^3.
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LINKS
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PROG
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(PARI) {a(n)=local(Rn=y^3); for(m=3, n-1, Rn=subst(truncate(Rn), y, y+y^2+O(y^m))); subst(truncate(Rn), y, 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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