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%I #4 Mar 31 2012 13:21:56
%S 3,4,7,8,9,10,12,13,16,17,19,20,21,22,24,25,26,27,28,29,30,31,33,34,
%T 35,36,37,38,39,40,41,42,44,45,46,47,48,49,50,51,52,53,54,55,56,58,59,
%U 60,61,62,63,65,66,67,68,69,70,71,73,75,76,77,78,81,82,83,84,85,86,87,89
%N Numbers n such that sigma(n) can be represented as sum{i=0,k, sigma(m+i)}, with k>0.
%C Is it true that every integer n ultimately has sigma(n) representable like this?
%e sigma(61)=62=sigma(13)+sigma(14)+sigma(15)=14+24+24
%o (PARI) { s=vector(1000); sc=0; for (k=1,10, for (i=1,100,s[sc++ ]=sum(j=0,k, sigma(i+j)))); s=vecsort(s); s } for (i=2,100, for (j=1,1000,if (sigma(i)==s[j],print1(i","); break)))
%Y Cf. A086987 gives values of sigma.
%K nonn
%O 1,1
%A _Jon Perry_, Jul 27 2003
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