A127195 Number of subsets of {1,2,...,n} which contain no three consecutive odd numbers.

2, 4, 8, 16, 28, 56, 104, 208, 384, 768, 1408, 2816, 5184, 10368, 19072, 38144, 70144, 140288, 258048, 516096, 949248, 1898496, 3491840, 6983680, 12845056, 25690112, 47251456, 94502912, 173817856, 347635712, 639401984, 1278803968

Offset

1,1

Links

Table of n, a(n) for n=1..32.

Formula

a(n) = A000073(floor((n+1)/2)-3) * 2^(floor(n/2)).

Crossrefs

Sequence in context: A308542 A326116 A054189 * A255937 A357763 A330289

Adjacent sequences: A127192 A127193 A127194 * A127196 A127197 A127198

Keyword

easy,nonn

Author

FUNG Cheok Yin, Mar 27 2007

Extensions

Offset corrected by Joerg Arndt, Mar 03 2017

Status

approved