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 A342698 For any number n with binary expansion (b(1), b(2), ..., b(k)), the binary expansion of a(n) is (floor((b(k)+b(1)+b(2))/2), floor((b(1)+b(2)+b(3))/2), ..., floor((b(k-1)+b(k)+b(1))/2). 4
 0, 1, 1, 3, 0, 7, 7, 7, 0, 9, 5, 15, 12, 15, 15, 15, 0, 17, 1, 19, 8, 27, 15, 31, 24, 25, 29, 31, 28, 31, 31, 31, 0, 33, 1, 35, 0, 35, 7, 39, 16, 49, 21, 55, 28, 63, 31, 63, 48, 49, 49, 51, 56, 59, 63, 63, 56, 57, 61, 63, 60, 63, 63, 63, 0, 65, 1, 67, 0, 67, 7 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,4 COMMENTS This sequence is a variant of A342697; here we deal with bit triples in a "cyclic" binary representation of n. LINKS Rémy Sigrist, Table of n, a(n) for n = 0..8192 FORMULA a(n) + A342700(n) = A003817(n). a(n) = n iff n belongs to A342699. EXAMPLE The first terms, in decimal and in binary, are:   n   a(n)  bin(n)  bin(a(n))   --  ----  ------  ---------    0     0       0          0    1     1       1          1    2     1      10          1    3     3      11         11    4     0     100          0    5     7     101        111    6     7     110        111    7     7     111        111    8     0    1000          0    9     9    1001       1001   10     5    1010        101   11    15    1011       1111   12    12    1100       1100   13    15    1101       1111   14    15    1110       1111   15    15    1111       1111 PROG (PARI) a(n) = my (w=#binary(n)); sum(k=0, w-1, ((bittest(n, (k-1)%w)+bittest(n, k%w)+bittest(n, (k+1)%w))>=2) * 2^k) CROSSREFS Cf. A003817, A342697, A342699 (fixed points), A342700. Sequence in context: A201900 A344387 A019970 * A239022 A343612 A198488 Adjacent sequences:  A342695 A342696 A342697 * A342699 A342700 A342701 KEYWORD nonn,base AUTHOR Rémy Sigrist, Mar 18 2021 STATUS approved

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Last modified May 28 05:47 EDT 2022. Contains 354112 sequences. (Running on oeis4.)