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A278588 Triangle read by rows: T(p_1,p_2) = maximal period of a decimal fraction (r/s)*(t/u) given that r/s has period p_1 and t/u has period p_2 (1 <= p_1 <= p_2).

%I A278588 #27 Jul 09 2025 04:42:20
%S A278588 9,18,198,27,54,2997,36,396,108,39996,45,90,135,180,499995,54,594,
%T A278588 5994,3564,270,5999994,63,126,189,252,315
%N A278588 Triangle read by rows: T(p_1,p_2) = maximal period of a decimal fraction (r/s)*(t/u) given that r/s has period p_1 and t/u has period p_2 (1 <= p_1 <= p_2).
%H A278588 Arnout Jaspers, <a href="https://www.pyth.eu/uploads/user/ArchiefPDF/Pyth55-5.pdf">Megaperiodieke Breuken Maken</a>, Pythagoras, Number 5, April 2016, pp. 26-29.
%H A278588 Arnout Jaspers, <a href="/A278588/a278588.txt">Creating Mega-Periodic Fractions</a> (Loose English translation from _R. J. Mathar_).
%e A278588 Triangle begins (read down columns):
%e A278588 ...1.....2....3....4....5.....6......7....(p_2)
%e A278588 1..9....18...27...36...45....54.....63
%e A278588 2......198...54..396...90...594....126
%e A278588 3..........2997..108..135..5994....189
%e A278588 4..............39996..180..3564....252
%e A278588 5..................499995...270....315
%e A278588 ...
%e A278588 (p_1)
%Y A278588 Cf. A110807 (diagonal?)
%K A278588 nonn,tabl
%O A278588 1,1
%A A278588 _N. J. A. Sloane_, Dec 03 2016, based on English translations provided by _Arie Bos_ and _R. J. Mathar_