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[ (3rd elementary symmetric function of S(n))/(2nd elementary symmetric function of S(n)) ], where S(n) = {first n+2 positive integers congruent to 1 mod 4}.
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%I #13 Jul 06 2019 20:59:42

%S 3,7,12,18,26,35,46,58,71,86,101,119,137,157,178,201,225,250,276,304,

%T 334,364,396,429,464,500,537,575,615,657,699,743,788,835,883,932,982,

%U 1034,1088,1142,1198,1255,1314,1374,1435,1497,1561,1627,1693,1761,1830

%N [ (3rd elementary symmetric function of S(n))/(2nd elementary symmetric function of S(n)) ], where S(n) = {first n+2 positive integers congruent to 1 mod 4}.

%F Empirical g.f.: x*(x^20 -2*x^19 +x^18 +x^12 -2*x^11 +x^10 +x^9 -x^8 -x^7 -2*x^6 -x^5 -2*x^4 -x^3 -x^2 -x -3) / ((x -1)^3*(x^2 +x +1)*(x^6 +x^3 +1)). - _Colin Barker_, Aug 16 2014

%F a(n) = floor(A024379(n + 1) / A024378(n + 2)). - _Sean A. Irvine_, Jul 06 2019

%K nonn,easy

%O 1,1

%A _Clark Kimberling_

%E More terms from _Joshua Zucker_, May 20 2006