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%I #10 Sep 11 2019 06:58:23
%S 1,12,18,24,32,42,60,72,90,140,168,224,234,252,312,360,468,480,576,
%T 588,600,684,702,720,728,744,840,864,992,1092,1232,1240,1260,1344,
%U 1440,1488,1512,1560,1860,1872,2016,2240,2340,2352,2418,2688,2730,2880,3360,3528
%N Number m that give records for the difference between the maximum and minimum x's such that sigma(x)=m.
%H Amiram Eldar, <a href="/A241852/b241852.txt">Table of n, a(n) for n = 1..1000</a>
%e Only sigma(1)=1, hence the first difference is 0.
%e The next m with several x's is 12 with sigma(6)=sigma(11)=12, difference 5 is > 0.
%o (PARI) sigv(n) = select(i->sigma(i) == n, vector(n, i, i));
%o ds(n) = {v = sigv(n); if (#v == 0, 0, vecmax(v) - vecmin(v)); }
%o lista(nn) = {dmax = -1; for (n=1, nn, if ((dv = ds(n)) > dmax, print1(n, ", "); dmax = dv;););}
%Y Cf. A241853 (corresponding differences), A241854 (similar but with quotients).
%K nonn
%O 1,2
%A _Michel Marcus_, Apr 30 2014
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