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%I #4 Mar 13 2015 00:57:25
%S 4,8,11,14,17,20,75,85,95,105,36,39,135,145,155,165,553,58,616,648,
%T 680,711,743,77,806,838,869,901,933,96,996,1028,1059,1091,1122,1154,
%U 1186,1217,1249,4050,1312,1344,1375,1407,4550,1470,1502,4850,1565,5050
%N Index of smallest triangular number beginning with the n-th triangular number other than itself.
%e a(7) = 75 as the 75th triangular number 2850 > 28 is the smallest triangular number beginning with 28 which is the seventh triangular number.
%Y Cf. A072517.
%K base,nonn
%O 1,1
%A _Amarnath Murthy_, Jul 31 2002
%E Corrected and extended by Antonio G. Astudillo (afg_astudillo(AT)lycos.com), Apr 25 2003