A089889 Number of subsets of {1,.., n} containing exactly one square.

1, 2, 4, 8, 16, 32, 64, 128, 192, 384, 768, 1536, 3072, 6144, 12288, 16384, 32768, 65536, 131072, 262144, 524288, 1048576, 2097152, 4194304, 5242880, 10485760, 20971520, 41943040, 83886080, 167772160, 335544320, 671088640, 1342177280

Offset

1,2

Comments

a(n)=A000196(n)*A089887(n);

for n>1: a(n) = A089886(n,1).

Links

Table of n, a(n) for n=1..33.

Formula

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

Crossrefs

Cf. A089890.

Sequence in context: A327368 A286660 A009641 * A297526 A229617 A306316

Adjacent sequences: A089886 A089887 A089888 * A089890 A089891 A089892

Keyword

nonn

Author

Reinhard Zumkeller, Nov 13 2003

Status

approved