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A110552
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A triangular array related to A077028 and distributing the values of A007582.
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1
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1, 1, 2, 1, 5, 4, 1, 10, 17, 8, 1, 19, 51, 49, 16, 1, 36, 134, 196, 129, 32, 1, 69, 330, 650, 645, 321, 64, 1, 134, 783, 1940, 2575, 1926, 769, 128, 1, 263, 1813, 5411, 8995, 8981, 5383, 1793, 256, 1, 520, 4124, 14392, 28742, 35896, 28700, 14344, 4097, 512, 1, 1033, 9252, 36948, 86142, 129150, 129108, 86052, 36873, 9217, 1024
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OFFSET
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1,3
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COMMENTS
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Let T(r,c) be the array A077028. Fill 2^k numbers in Gaussian templates conforming to the row lengths determined by T(r,c). A110552 results from summing the numbers on each row.
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LINKS
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FORMULA
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Table entries appear to be given by T(n,k) = binomial(n-2,k-1) + 2^(n-1)*binomial(n-2,k-2), n,k >= 1, leading to the e.g.f. (exp((1+x)*u) - 1)*(x*exp((1+x)*u) + x + 2)/(2*(1+x)^2) = u + (1+2*x)*u^2/2! + (1+5*x+4*x^2)*u^3/3! + .... Cf. A111049. - Peter Bala, Jul 27 2012
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EXAMPLE
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The filled templates begin
1
.1
.2
..1
..2.3
..4
....1
....2.3.5
....4.6.7
....8
therefore the sequence begins
1
1 2
1 5 4
1 10 17 8
...
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MATHEMATICA
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T[n_, k_] := Binomial[n - 2, k - 1] + 2^(n - 1)*Binomial[n - 2, k - 2]; Table[T[n, k], {n, 1, 20}, {k, 1, n}] // Flatten (* G. C. Greubel, Aug 31 2017 *)
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PROG
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(PARI) for(n=1, 20, for(k=1, n, print1(binomial(n - 2, k - 1) + 2^(n - 1)*binomial(n - 2, k - 2), ", "))) \\ G. C. Greubel, Aug 31 2017
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CROSSREFS
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KEYWORD
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AUTHOR
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STATUS
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approved
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