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A182140 Numbers n such that A060968(n) = A201629(n).

%I A182140 #36 Sep 26 2015 22:43:58
%S A182140 2,3,5,7,11,13,15,17,19,23,29,31,37,41,43,47,53,59,61,67,71,73,79,83,
%T A182140 89,97,101,103,107,109,113,127,131,137,139,143,149,151,157,163,167,
%U A182140 173,179,181,191,193,197,199,211,223,227,229,233,239,241,251,255,257
%N A182140 Numbers n such that A060968(n) = A201629(n).
%C A182140 Includes prime numbers and the sequence A071700.
%C A182140 a(n) = A240960(n) for n <= 35. - _Reinhard Zumkeller_, Aug 05 2014
%H A182140 Charles R Greathouse IV, <a href="/A182140/b182140.txt">Table of n, a(n) for n = 1..10000</a>
%t A182140 fa = FactorInteger; A060968[p_, s_] := Which[Mod[p, 4] == 1, p^( s - 1)*(p - 1), Mod[p, 4] == 3, p^(s - 1)*(p + 1), s == 1,2, True, 2^(s + 1)]; A060968[1] = 1; A060968[n_] := Product[A060968[fa[n][[i, 1]], fa[n][[i, 2]]], {i, Length[fa[n]]}]; A201629[n_] := Which[Mod[n, 4] == 1, (n - 1), Mod[n, 4] == 3, (n + 1), True, n]; Select[Range[1000], A060968[#] == A201629[#] &]
%o A182140 (PARI) is(n)=my(f=factor(n)[, 1]); n*prod(i=if(n%2, 1, 2), #f, if(f[i]%4==1, 1-1/f[i], 1+1/f[i]))*if(n%4, 1, 2)==if(n%2,(n+1)\4*4,n) \\ _Charles R Greathouse IV_, Jul 03 2013
%o A182140 (Haskell)
%o A182140 a182140 n = a182140_list !! (n-1)
%o A182140 a182140_list = [x | x <- [1..], a060968 x == a201629 x]
%o A182140 -- _Reinhard Zumkeller_, Aug 05 2014
%Y A182140 Cf. A060968, A201629, A071700, A240960.
%K A182140 nonn
%O A182140 1,1
%A A182140 _José María Grau Ribas_, Apr 14 2012