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%I #9 Jun 19 2019 04:16:47
%S 28,72,77,102,143,150,171,238,247,248,319,357,368,390,434,490,500,513,
%T 533,578,656,667,682,817,825,852,858,875,943,1054,1073,1092,1113,1207,
%U 1225,1300,1312,1320,1333,1358,1472,1575,1598,1690,1691,1736,1738,1862,1887,1900,1943
%N Integers k such that A308702(k) < k-1.
%C In many cases A308702(n), the least integer m such that m^2+2*n-1 and m^2+4*n is the trivial solution: m = n-1.
%C So this sequence lists the integers k for which a smaller m can be found.
%H Michel Marcus, <a href="/A308703/b308703.txt">Table of n, a(n) for n = 1..500</a>
%o (PARI) isok2(m, k) = issquare(m) && issquare(m+k-1) && issquare(m+2*k);
%o findm(k) = my(m=1); while (!isok2(m^2,k), m++); m;
%o least(n) = findm(2*n); \\ A308702
%o isok(n) = least(n) != (n-1);
%Y Cf. A000290 (squares), A308702.
%K nonn
%O 1,1
%A _Michel Marcus_, Jun 18 2019