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A111413
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a(n) = f(f(n+1))-f(f(n)), where f(m) = Euler(m) = A000111(m).
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1
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OFFSET
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0,4
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LINKS
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MAPLE
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b:= proc(u, o) option remember;
`if`(u+o=0, 1, add(b(o-1+j, u-j), j=1..u))
end:
a:= n-> (f-> f(f(n+1))-f(f(n)))(k-> b(k, 0)):
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MATHEMATICA
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$RecursionLimit = Infinity;
t[n_, 0] := Boole[n == 0];
t[n_, k_] := t[n, k] = t[n, k-1] + t[n-1, n-k];
f[n_] := t[n, n];
a[n_] := f[f[n+1]] - f[f[n]];
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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