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A158745
a(3n)=A130750(n). a(3n+1)=A130752(n). a(3n+2)=A130755(n).
1
1, 2, 3, 3, 5, 4, 8, 9, 7, 17, 16, 15, 33, 31, 32, 64, 63, 65, 127, 128, 129, 255, 257, 256, 512, 513, 511, 1025, 1024, 1023, 2049, 2047, 2048, 4096, 4095, 4097, 8191, 8192, 8193, 16383, 16385, 16384, 32768, 32769, 32767, 65537, 65536, 65535, 131073, 131071, 131072, 262144
OFFSET
0,2
COMMENTS
This mixes three sequences which are identical to their third differences.
LINKS
FORMULA
a(3n)+a(3n+1)+a(3n+2)= A007283(n+1).
a(18n) = A130750(6n)= 2^(6n+1)-1.
a(n) = 3*a(n-3)-3*a(n-6)+2*a(n-9). G.f.: -(1+2*x+3*x^2-x^4-5*x^5+2*x^6+4*x^8)/((2*x^3-1)*(x^6-x^3+1)). - R. J. Mathar, Jan 23 2009
MATHEMATICA
LinearRecurrence[{0, 0, 3, 0, 0, -3, 0, 0, 2}, {1, 2, 3, 3, 5, 4, 8, 9, 7}, 60] (* Harvey P. Dale, Mar 12 2023 *)
CROSSREFS
KEYWORD
nonn,less
AUTHOR
Paul Curtz, Mar 25 2009
EXTENSIONS
Edited and extended by R. J. Mathar, Apr 09 2009
STATUS
approved