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Numbers k such that anti-phi(k) = anti-phi(k+1).
1

%I #18 Jul 19 2022 05:47:47

%S 2,8,14,20,27,32,284,297,362,717,842,1322,1377,1725,1802,1917,1982,

%T 2222,2637,3410,4094,4149,4850,5288,5642,5654,5660,5690,5750,5937,

%U 5949,6237,7017,7245,7377,7490,8097,8217,8277,8462,8774,9117,9542,9897,10034,11409,11810

%N Numbers k such that anti-phi(k) = anti-phi(k+1).

%C Like A001274 but using anti-phi, as defined in A066452, instead of phi, per A000010.

%H Amiram Eldar, <a href="/A241003/b241003.txt">Table of n, a(n) for n = 1..512</a>

%e anti-phi(2) = anti-phi(3) = 1.

%e anti-phi(8) = anti-phi(9) = 4.

%e anti-phi(14) = anti-phi(15) = 7. Etc.

%p for n from 1 do

%p if A066452(n) = A066452(n+1) then

%p printf("%d,\n",n);

%p end if;

%p end do: # _R. J. Mathar_, Aug 07 2014

%Y Cf. A000010, A001274, A066418, A066452.

%K nonn

%O 1,1

%A _Paolo P. Lava_, Aug 07 2014