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%I #4 Mar 30 2012 18:40:58
%S 1264460,3379784,6164364,11102500,18271604,36320580,54976960,83135125,
%T 129857825,210986457,385264277,594788487,924792067,1423007483,
%U 2659409715,4458691045,6846467595,9563962830,12443660134,16149431959
%N Partials sums of A090615.
%C Partials sums of smallest member of sociable quadruples. Primes in this partial sum begin: 924792067, 16149431959.
%H Eric W. Weisstein, <a href="http://mathworld.wolfram.com/SociableNumbers.html">Sociable Numbers</a>
%F a(n) = sum[i=1..n] A090615(i).
%e a(13) = 1264460 + 2115324 + 2784580 + 4938136 + 7169104 + 18048976 + 18656380 + 28158165 + 46722700 + 81128632 + 174277820 + 209524210 + 330003580 = 924792067 is prime.
%Y Cf. A090615.
%K nonn,less
%O 1,1
%A _Jonathan Vos Post_, Sep 13 2010