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%I #13 Jan 16 2017 14:23:27
%S 1,4,9,4,2,12,49,11,3,40,26,60,1,11,225,112,5,144,43,12,6,220,21,18,7,
%T 32,60,364,8,420,961,4,9,25,77,612,10,16,243,760,2,840,94,4,12,1012,
%U 165,81,13,52,111,1300,14,24,340,67,15,1624,9,1740,16,35,3969,46
%N Least number k such that Sum_{j=k..k+n-1}{j} = Sum_{j=k+n..t}{j}, for some t >= k+n.
%C With n = 5 consecutive numbers we can start from k = 4 but also from k = 16. The sequence considers only the least number: a(5) = 4.
%H Paolo P. Lava, <a href="/A281152/a281152_1.txt">First 500 terms with values for n, k and t</a>
%e a(2)= 1 because 1+2=3 and 1 is the least number to have this property;
%e a(3)= 4 because 4+5+6=7+8 and 4 is the least number to have this property;
%e a(4)= 9 because 9+10+11+12=13+14+15 and 9 is the least number to have this property;
%e a(5)= 4 because 4+5+6+7+8=9+10+11 and 4 is the least number to have this property.
%p P:=proc(q,h) local a,b,c,j,k,n; for n from 2 to q do for k from 1 to q do a:=add(j^h,j=k..k+n-1); b:=0;
%p c:=k+n-1; while b<a do c:=c+1; b:=b+c^h; od; if a=b then print(k); break; fi; od; od; end: P(10^6,1);
%Y Cf. A281153.
%K nonn,easy
%O 2,2
%A _Paolo P. Lava_, Jan 16 2017
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