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%I #8 Aug 05 2019 02:06:15
%S 1,7,20,39,64,95,133,177,227,284,346,415,489,570,657,750,849,954,1065,
%T 1182,1305,1434,1569,1710,1857,2010,2169,2334,2505,2682,2865,3054,
%U 3249,3450,3657,3870,4089,4314,4545,4782,5025,5274,5529,5790,6057,6330,6609,6894
%N a(n) = position of 3*n^2 in sequence A025051 (numbers of form j*k + k*i + i*j, without repetitions, where 1 <= i <= j <= k).
%Y Cf. A025051.
%K nonn
%O 1,2
%A _Clark Kimberling_
%E a(5) onward corrected and more terms from _Sean A. Irvine_, Aug 05 2019