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%I #8 Mar 09 2022 09:40:00
%S 57456,80752,124852,229957,355072,366471,630667,919296,1193200,
%T 1292032,1316875,1371136,1823472,1997632,2036097,2687607,3679312,
%U 4251871,4653936,5681152,5821552,5863536,6540912,8905456,8984196,10090672,10113012,10504375,10532592,10789632,10921456,14708736
%N Positive integers that can be expressed in at least two ways as (x-y)*(x^3-y^3).
%C Integers that appears at least twice in the A352242 triangle.
%e 57456 is a term since it is A352242(17,5) as well as A352242(26,20).
%o (PARI) row(n) = vector(n-1, k, (n-k)*(n^3-k^3));
%o lista(nn) = {my(list = List(), n=2); while (3*n*(n-1)+1 <= nn, my(rown = row(n)); for (k=1, #rown, if (rown[k] <= nn, listput(list, rown[k]))); n++;); listsort(list); my(res = List()); for (n=1, #list, if (#select(x->(x==list[n]), list) > 1, if (!vecsearch(Vec(res), list[n]), listput(res, list[n])));); Vec(res);}
%Y Cf. A352242, A352243.
%K nonn
%O 1,1
%A _Michel Marcus_, Mar 09 2022, after a suggestion from Vincent Thill
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