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A327874
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Number of length n primitive (aperiodic) palindromes with integer entries that cover an initial interval of positive integers.
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3
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1, 1, 0, 2, 2, 12, 10, 74, 72, 538, 528, 4682, 4668, 47292, 47218, 545820, 545760, 7087260, 7086710, 102247562, 102247020, 1622632496, 1622627890, 28091567594, 28091562840, 526858348368, 526858301088, 10641342969902, 10641342923148, 230283190977852, 230283190431480
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OFFSET
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0,4
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LINKS
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FORMULA
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a(n) = Sum_{d|n} mu(n/d)*A000670(ceiling(d/2)) for n > 0.
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PROG
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(PARI) a(n) = {if(n<1, n==0, sumdiv(n, d, moebius(n/d)*sum(k=1, ceil(d/2), k!*stirling(ceil(d/2), k, 2))))}
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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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