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%I #19 Aug 11 2021 09:21:23
%S 8,11,14,15,17,19,20,23,24,26,27,29,31,32,34,35,38,39,41,43,44,47,48,
%T 49,50,51,53,54,55,56,59,62,63,64,65,67,68,69,71,74,75,76,77,79,80,83,
%U 84,86,87,89,90,91,92,94,95,97,98,99,101,103,104,107,109,110,111,113
%N Numbers that can be represented as x * y + x + y, where x >= y > 1.
%C Apparently 8 and the elements of A061743. - _R. J. Mathar_, Feb 19 2015
%e 14 = 2 * 4 + 2 + 4.
%e 15 = 3 * 3 + 3 + 3.
%e There is no way to express 16 in this form, so it is not in the sequence.
%t sol[t_] := Solve[x >= y > 1 && x y + x + y == t, {x, y}, Integers];
%t Select[Range[200], sol[#] != {}&] (* _Jean-François Alcover_, Jul 28 2020 *)
%o (Python)
%o def aupto(limit):
%o cands = range(2, limit//3+1)
%o nums = [x*y+x+y for i, y in enumerate(cands) for x in cands[i:]]
%o return sorted(set(k for k in nums if k <= limit))
%o print(aupto(113)) # _Michael S. Branicky_, Aug 11 2021
%Y Cf. A254636 is the complement.
%K nonn
%O 1,1
%A _Alex Ratushnyak_, Feb 04 2015
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