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A112058 Mean of A112056 and A112057. 4

%I

%S 48,72,120,168,192,288,312,360,408,432,480,528,552,648,672,720,768,

%T 792,840,888,912,960,1008,1032,1128,1152,1200,1248,1272,1320,1368,

%U 1392,1488,1512,1560,1608,1632,1680,1728,1752,1800,1848,1872,1968

%N Mean of A112056 and A112057.

%F a(n) = 4*A112054(n).

%t a112046[n_]:=Block[{i=1}, While[JacobiSymbol[i, 2n + 1]==1, i++]; i]; 4*Select[Range[1000], a112046[2#] - a112046[2# - 1] != 0 &] (* _Indranil Ghosh_, May 24 2017 *)

%o (Python)

%o from sympy import jacobi_symbol as J

%o def a112046(n):

%o i=1

%o while True:

%o if J(i, 2*n + 1)!=1: return i

%o else: i+=1

%o def a(n): return a112046(2*n) - a112046(2*n - 1)

%o print([4*n for n in range(1, 1001) if a(n)!=0]) # _Indranil Ghosh_, May 24 2017

%Y a(n) = A112056(n)+1 = A112057(n)-1 = (A112056(n)+A112057(n))/2.

%K nonn

%O 1,1

%A _Antti Karttunen_, Aug 27 2005

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Last modified September 23 19:48 EDT 2021. Contains 347617 sequences. (Running on oeis4.)