1,2

a(n) = Sum(A089886(n,k): 1<=k<=A000196(n)) = A000079(n)-A089887(n) = A089887(n)*A000225(A000196(n)).

a(n) = (2^(n^(1/2))-n^(1/2))*2^(n-1).

Cf. A089890.

Sequence in context: A108720 A089822 A079352 this_sequence A133411 A004645 A045687

Adjacent sequences: A089885 A089886 A089887 this_sequence A089889 A089890 A089891

nonn

Reinhard Zumkeller (reinhard.zumkeller(AT)lhsystems.com), Nov 13 2003