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%I #12 Oct 09 2019 07:49:27
%S 5,1,2,9,11,25,418,1062,131,878,2442,1125,938,2422,1184,1212,1388,
%T 2349,1287,1113,2649,1623,2457,1375,1713,2377,1464,3689,1035,2448,
%U 7890,10706,1312,17147,18793,19616,22072,11858,26504,47051,15775,14952
%N Triples (a,b,c) such that (a+b+c)^3 = concat(a,b,c), a, b, c > 0, ordered by size of this value.
%C The sequence can be considered as a table with rows of length 3, row(n) = a(3n-2 .. 3n).
%C A variant of Kaprekar and pseudo-Kaprekar triples, cf. A006887 and A060768.
%C See A328198 and A328200 (sequence of the values a+b+c and concatenated triples) for more information.
%H Giovanni Resta, <a href="/A328199/b328199.txt">Table of n, a(n) for n = 1..717</a>
%H Números y algo mas, <a href="https://www.facebook.com/permalink.php?story_fbid=2467527383315339&id=126559577412143">9 + 11+ 25 = 91125^(1/3) etc</a>, post on facebook.com, Sep 30 2019.
%e 5+1+2 = 512^(1/3) = 8,
%e 9+11+25 = 91125^(1/3) = 45,
%e 418+1062+131 = (4181062131)^(1/3) = 1611, ...
%o (PARI) is(n,Ln=A055642(n),n3=n^3,Ln3=A055642(n3))={my(ab,c); for(Lc=Ln3-2*Ln,Ln, [ab,c]=divrem(n3, 10^Lc); n-c<10^(Ln-1) || c < 10^(Lc-1) || for( Lb=Ln3-Ln-Lc,Ln, vecsum(divrem(ab,10^Lb)) == n-c && ab%10^Lb>=10^(Lb-1)&& return(concat(divrem(ab,10^Lb)~,c))))} \\ A055642(n)=logint(n,10)+1 = #digits(n)
%o for( Ln=1,oo, for( n=10^(Ln-1),10^Ln-1, (t=is(n,Ln))&& print1(t", ")))
%Y Cf. A328198 (row sums), A328200 (rows concatenated), A006887 & A291461 (Kaprekar numbers), A060768 (pseudo Kaprekar numbers); A000578 (the cubes), A055642 (number of digits of n).
%K nonn,base,tabf
%O 1,1
%A _M. F. Hasler_, Oct 07 2019
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