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A353467
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a(1) = 1, for n > 1, a(n) = -Sum_{d|n, d<n} a(A252463(n/d)) * a(d).
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5
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1, -1, 1, 2, -1, -3, 1, -5, -1, 3, -1, 10, 1, -3, 1, 14, -1, 0, 1, -10, -1, 3, -1, -35, 2, -3, 2, 10, 1, 3, -1, -42, 1, 3, -3, 10, 1, -3, -1, 35, -1, -3, 1, -10, -3, 3, -1, 126, -1, -9, 1, 10, 1, -1, 3, -35, -1, -3, -1, -30, 1, 3, 3, 132, -3, 3, -1, -10, 1, 15, 1, -70, -1, -3, -1, 10, 1, -3, 1, -126, -5, 3, -1, 30
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OFFSET
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1,4
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LINKS
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FORMULA
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a(1) = 1, for n > 1, a(n) = -Sum_{d|n, d<n} A353468(n/d) * a(d).
For all n >= 1, a(A000040(n)) = ((-1)^n).
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PROG
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(PARI)
A252463(n) = if(!(n%2), n/2, my(f=factor(n)); for(i=1, #f~, f[i, 1] = precprime(f[i, 1]-1)); factorback(f));
memoA353467 = Map();
A353467(n) = if(1==n, 1, my(v); if(mapisdefined(memoA353467, n, &v), v, v = -sumdiv(n, d, if(d<n, A353467(A252463(n/d))*A353467(d), 0)); mapput(memoA353467, n, v); (v)));
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CROSSREFS
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KEYWORD
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sign
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AUTHOR
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STATUS
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approved
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