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A127195
Number of subsets of {1,2,...,n} which contain no three consecutive odd numbers.
0
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
FORMULA
a(n) = A000073(floor((n+1)/2)-3) * 2^(floor(n/2)).
CROSSREFS
Sequence in context: A308542 A326116 A054189 * A255937 A357763 A330289
KEYWORD
easy,nonn
AUTHOR
FUNG Cheok Yin, Mar 27 2007
EXTENSIONS
Offset corrected by Joerg Arndt, Mar 03 2017
STATUS
approved