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A177882 Trisection of A001317. 5
1, 15, 85, 771, 4369, 65535, 327685, 3342387, 16843009, 252645135, 1431655765, 12884901891, 73014444049, 1095216660735, 5519032976645, 56294136361779, 281479271743489, 4222189076152335, 23925738098196565 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,2
COMMENTS
For n>=1, all terms are in A001969.
Or rows of triangle A008287 mod 2 converted to decimal.
LINKS
FORMULA
a(n) = A001317(3*n).
MATHEMATICA
f[n_] := BitXor[n, BitShiftLeft[n, 1]]; Table[Nest[f, 1, x], {x, 0, 54, 3}]
PROG
(PARI)
a(n) = subst(lift(Pol(Mod([1, 1, 1, 1], 2), 'x)^n), 'x, 2);
vector(19, n, a(n-1)) \\ Gheorghe Coserea, Jun 12 2016
(Python)
def A177882(n): return sum((bool(~(3*n)&3*n-k)^1)<<k for k in range(3*n+1)) # Chai Wah Wu, May 02 2023
CROSSREFS
Sequence in context: A064058 A138322 A206170 * A199897 A367228 A309922
KEYWORD
nonn
AUTHOR
Vladimir Shevelev, Dec 14 2010
EXTENSIONS
Definition rewritten by N. J. A. Sloane, Jan 01 2011
STATUS
approved

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Last modified April 29 22:06 EDT 2024. Contains 372114 sequences. (Running on oeis4.)