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 A007461 Shifts left under AND-convolution with itself. (Formerly M0117) 4
 1, 1, 2, 1, 2, 4, 0, 5, 2, 4, 0, 10, 0, 12, 4, 13, 6, 12, 0, 18, 12, 20, 20, 36, 20, 36, 16, 44, 32, 60, 40, 73, 50, 56, 40, 58, 44, 52, 60, 84, 36, 112, 88, 108, 136, 132, 152, 178, 136, 232, 108, 260, 244, 256, 304, 288 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 COMMENTS a(A000225(n)) mod 2 = 1, a(A062289(n)) mod 2 = 0. [Reinhard Zumkeller, Apr 02 2012] REFERENCES N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence). LINKS Reinhard Zumkeller, Table of n, a(n) for n = 0..10000 M. Bernstein and N. J. A. Sloane, Some canonical sequences of integers, Linear Alg. Applications, 226-228 (1995), 57-72; erratum 320 (2000), 210. [Link to arXiv version] M. Bernstein and N. J. A. Sloane, Some canonical sequences of integers, Linear Alg. Applications, 226-228 (1995), 57-72; erratum 320 (2000), 210. [Link to Lin. Alg. Applic. version together with omitted figures] MAPLE a:= proc(n) option remember; `if`(n=0, 1, add(       Bits[And](a(i), a(n-1-i)), i=0..n-1))     end: seq(a(n), n=0..80);  # Alois P. Heinz, Jun 16 2018 MATHEMATICA a[0]=1; a[1]=1; a[n_] := a[n] = Sum[BitAnd[a[k], a[n-k-1]], {k, 0, n-1}]; Table[a[n], {n, 0, 60}] (* Jean-François Alcover, Sep 07 2012 *) PROG (Haskell) import Data.Bits ((.&.)) a007461 n = a007461_list !! n a007461_list = 1 : f [1, 1] where    f xs = x : f (x:xs) where      x = sum \$ zipWith (.&.) xs \$ tail \$ reverse xs :: Integer -- Reinhard Zumkeller, Apr 02 2012 CROSSREFS Cf. A007460, A199770. Sequence in context: A265255 A131022 A137408 * A181302 A304785 A143446 Adjacent sequences:  A007458 A007459 A007460 * A007462 A007463 A007464 KEYWORD nonn,nice,eigen AUTHOR STATUS approved

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Last modified August 18 00:28 EDT 2018. Contains 313817 sequences. (Running on oeis4.)