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A080089 Let r+i*s be the sum of the first-quadrant Gaussian primes dividing prime(n); sequence gives s values. 4

%I #9 Feb 28 2020 04:12:39

%S 2,0,3,0,0,5,5,0,0,7,0,7,9,0,0,9,0,11,0,0,11,0,0,13,13,11,0,0,13,15,0,

%T 0,15,0,17,0,17,0,0,15,0,19,0,19,15,0,0,0,0,17,21,0,19,0,17,0,23,0,23,

%U 21,0,19,0,0,25,25,0,25,0,23,25,0,0,25,0,0,27,25,21,23,0,29,0,29,0,0,27,25

%N Let r+i*s be the sum of the first-quadrant Gaussian primes dividing prime(n); sequence gives s values.

%H Amiram Eldar, <a href="/A080089/b080089.txt">Table of n, a(n) for n = 1..10000</a>

%t s[n_] := Module[{f = FactorInteger[n, GaussianIntegers->True]}, p = f[[;;,1]]; e = f[[;;,2]]; Im[Plus @@ ((If[Abs[#]==1, 0, #]& /@ p) * e)]]; s /@ Select[ Range[100], PrimeQ] (* _Amiram Eldar_, Feb 28 2020 *)

%Y Cf. A078908, A078909, A080088.

%K nonn

%O 1,1

%A _Vladeta Jovovic_, Jan 27 2003

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