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A199397
Binary XOR of 3^k as k varies from 0 to n.
3
1, 2, 11, 16, 65, 178, 619, 2784, 4929, 24482, 47371, 133872, 659713, 1196754, 5945771, 8408000, 34643073, 94509378, 313886731, 1475558352, 2552700993, 12739900146, 24581737195, 70102639264, 350315469377, 639249412322, 3139708751627, 4623469310128, 18666316402561
OFFSET
0,2
COMMENTS
Appears to be a self-convolution of an integer sequence (true for at least the initial 761 terms).
LINKS
EXAMPLE
a(2) = 1 XOR 3 = 2; a(3) = 1 XOR 3 XOR 9 = 11; a(4) = 1 XOR 3 XOR 9 XOR 27 = 16.
MAPLE
A[0]:= 1:
for n from 1 to 40 do
A[n]:= Bits:-Xor(A[n-1], 3^n)
od:
seq(A[i], i=0..40); # Robert Israel, Nov 02 2015
MATHEMATICA
FoldList[BitXor, 3^Range[0, 28]] (* Vladimir Reshetnikov, Nov 02 2015 *)
PROG
(PARI) {a(n)=if(n<0, 0, bitxor(a(n-1), 3^n))}
CROSSREFS
Cf. A199396.
Sequence in context: A257283 A091211 A306278 * A012019 A012185 A012253
KEYWORD
nonn,base
AUTHOR
Paul D. Hanna, Nov 05 2011
STATUS
approved