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A095090
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Number of 4k+3 integers in range ]2^n,2^(n+1)] whose Jacobi-vector is a Motzkin-path (A095100).
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3
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1, 1, 2, 3, 6, 9, 17, 33, 60, 108, 202, 360, 703, 1328, 2519, 4779, 9103, 17501, 33473, 64761
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OFFSET
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1,3
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LINKS
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FORMULA
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a(n) = 2^(n-2) - A095091(n) for n > 1.
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PROG
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(PARI) is(m) = {my(s=0); for(i=1, m-1, if((s+=kronecker(i, m))<0, return(0))); 1; }
a(n) = {my(c=0); forstep(m=2^n+3-(n==1), 2^(n+1), 4, c+=is(m)); c; } \\ Jinyuan Wang, Jul 20 2020
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CROSSREFS
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KEYWORD
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nonn,more
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AUTHOR
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STATUS
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approved
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