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%I #12 Jun 15 2023 10:32:28
%S 1,12,18,28,30,38,42,48,60,72,102,108,138,150,168,180,192,228,240,270,
%T 282,312,348,402,420,432,462,522,570,600,618,642,660,732,768,798,810,
%U 858,882,990,1008,1020,1050,1092,1152,1218,1230,1278,1290,1320,1428,1452,1482,1608,1620,1722,1788,1830,1848
%N Numbers that set records in A360224.
%t s = Table[Count[Range[k], _?(Nor[CoprimeQ[#, k], GCD[k^2 - 1, #] > 1, Divisible[k, Times @@ FactorInteger[#][[All, 1]]]] &)], {k, 1000}]; Map[FirstPosition[s, #][[1]] &, Union@ FoldList[Max, s]]
%Y Cf. A360224, A361081.
%K nonn
%O 1,2
%A _Michael De Vlieger_, Jun 13 2023