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%I #12 Oct 23 2021 00:10:14
%S 64,144,224,304,324,384,464,504,544,624,684,704,784,864,944,1024,1044,
%T 1064,1104,1184,1224,1264,1344,1404,1424,1444,1504,1584,1624,1664,
%U 1744,1764,1824,1904,1944,1984,2064,2124,2144,2184,2204,2224,2304,2384,2464,2484,2544
%N Positive integers that are the product of two integers ending with 8.
%F Lim_{n->infinity} a(n)/a(n-1) = 1.
%e 64 = 8*8, 144 = 8*18, 224 = 8*28, 304 = 8*38, 324 = 18*18, 384 = 8*48, ...
%t a={}; For[n=0, n<=260, n++, For[k=0, k<=n, k++, If[Mod[10*n+4, 10*k+8]==0 && Mod[(10*n+4)/(10*k+8), 10]==8 && 10*n+4>Max[a], AppendTo[a, 10*n+4]]]]; a
%o (Python)
%o def aupto(lim): return sorted(set(a*b for a in range(8, lim//8+1, 10) for b in range(a, lim//a+1, 10)))
%o print(aupto(2550)) # _Michael S. Branicky_, Oct 22 2021
%Y Cf. A017317 (supersequence), A053742 (ending with 5), A139245 (ending with 2), A324297 (ending with 6), A346950 (ending with 3), A347253 (ending with 4), A348054 (ending with 7), A348549.
%K nonn,base
%O 1,1
%A _Stefano Spezia_, Oct 22 2021
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