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A367713
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G.f. A(x) satisfies A(x) = 1 / ((1 - x) * (1 - x * (1 + x) * A(x^2))).
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3
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1, 2, 4, 9, 20, 46, 105, 243, 560, 1296, 2994, 6928, 16019, 37060, 85713, 198282, 458636, 1060932, 2454070, 5676750, 13131210, 30374892, 70262196, 162528916, 375957183, 869654746, 2011661506, 4653323265, 10763942479, 24898869052, 57595401116, 133228161565
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OFFSET
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0,2
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LINKS
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FORMULA
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a(n) = 1 + Sum_{k=0..n-1} a(floor(k/2)) * a(n-1-k).
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PROG
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(PARI) a_vector(n) = my(v=vector(n+1)); for(i=0, n, v[i+1]=1+sum(j=0, i-1, v[j\2+1]*v[i-j])); v;
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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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