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A210680
a(n) = (3*a(n-1)) XOR a(n-2).
1
0, 1, 3, 8, 27, 89, 272, 873, 2859, 8936, 25491, 67665, 228192, 752241, 2167859, 6833896, 18464907, 52758345, 142005584, 440498361, 1186119547, 3461957320, 9357060899, 26968655777, 72945663424, 226371206881, 613739200867, 1752444795592, 4702791627067, 14623717009785
OFFSET
0,3
LINKS
FORMULA
a(n) = (3*a(n-1)) XOR a(n-2), a(0)=0, a(1)=1.
MATHEMATICA
RecurrenceTable[{a[0]==0, a[1]==1, a[n]==BitXor[3a[n-1], a[n-2]]}, a, {n, 30}] (* Harvey P. Dale, Nov 27 2014 *)
CROSSREFS
Cf. A168081: a(n) = (2*a(n-1)) XOR a(n-2), a(0)=0, a(1)=1.
Cf. A101624: a(n) = (2*a(n-2)) XOR a(n-1), a(0)=0, a(1)=1.
Cf. A204771: a(n) = (3*a(n-2)) XOR a(n-1), a(0)=0, a(1)=1.
Sequence in context: A029892 A148832 A148833 * A121650 A151462 A145967
KEYWORD
nonn,base,easy
AUTHOR
Alex Ratushnyak, May 09 2012
STATUS
approved