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Self-inverse integer permutation induced by Beatty sequences for 2*Pi and 2*Pi/(2*Pi-1).
5

%I #22 May 25 2022 11:29:08

%S 6,12,18,25,31,1,37,43,50,56,62,2,69,75,81,87,94,3,100,106,113,119,

%T 125,131,4,138,144,150,157,163,5,169,175,182,188,194,7,201,207,213,

%U 219,226,8,232,238,245,251,257,263,9,270,276,282,289,295,10,301,307,314,320,326,11,333,339,345,351,358,364,13,370

%N Self-inverse integer permutation induced by Beatty sequences for 2*Pi and 2*Pi/(2*Pi-1).

%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/BeattySequence.html">Beatty Sequence</a>

%H <a href="/index/Per#IntegerPermutation">Index entries for sequences that are permutations of the natural numbers</a>

%H <a href="/index/Be#Beatty">Index entries for sequences related to Beatty sequences</a>

%F a(A038130(n))=A108586(n) and a(A108586(n))=A038130(n).

%o (PARI) a30(n) = floor(n*2*Pi);

%o a86(n) = floor(2*n*Pi/(2*Pi-1));

%o lista(nn) = {my(vb = vector(nn, n, a30(n))); my(vc = vector(nn, n, a86(n))); my(va = vector(nn)); for (n=1, nn, if (vb[n] <= nn, va[vb[n]] = vc[n]); if (vc[n] <= nn, va[vc[n]] = vb[n]);); va;} \\ _Michel Marcus_, May 25 2022

%Y Cf. A108590, A108591, A108593.

%K nonn,easy

%O 1,1

%A _Reinhard Zumkeller_, Jun 11 2005

%E Four terms corrected by _Georg Fischer_ and _Michel Marcus_, May 25 2022