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A078912
a(1)=a(2)=1, a(n)=a(n-1)+a(n-2) if n is odd, a(n)=a(n-1)+a(n/2) if n is even.
0
1, 1, 2, 3, 5, 7, 12, 15, 27, 32, 59, 66, 125, 137, 262, 277, 539, 566, 1105, 1137, 2242, 2301, 4543, 4609, 9152, 9277, 18429, 18566, 36995, 37257, 74252, 74529, 148781, 149320, 298101, 298667, 596768, 597873, 1194641, 1195778, 2390419, 2392661
OFFSET
1,3
FORMULA
a(2n) is asymptotic to c*2^n and a(2n+1) to c*2^(n+1) where c=1.14147011562626318730578487228102392422856384213213612463664....
PROG
(PARI) a(n)=if(n<3, 1, a(n-1)+if(n%2, a(n-2), a(n/2)))
CROSSREFS
Sequence in context: A113623 A308868 A361459 * A105930 A122622 A266775
KEYWORD
nonn
AUTHOR
Benoit Cloitre, Jan 11 2003
STATUS
approved