1,4

a(n) = A000217(A000196(n)-1)*A089887(n);

for n>2: a(n) = A089886(n,2).

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

Cf. A089889.

Sequence in context: A046055 A020707 A049934 this_sequence A049932 A020161 A068890

Adjacent sequences: A089887 A089888 A089889 this_sequence A089891 A089892 A089893

nonn

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