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A377439 Least integer k which, by a process analogous to the Keith numbers, reach k - n.

%I A377439 #9 Sep 02 2025 04:36:41
%S A377439 14,18,10,11,12,10,11,10,10,10,20,27,22,25,20,23,20,21,20,38,32,30,31,
%T A377439 34,30,32,31,30,40,47,41,45,40,43,42,41,40,58,51,56,50,54,53,52,51,50,
%U A377439 61,67,60,65,64,63,62,61,60,78,70,76,75,74,73,72,71,70,80,87
%N A377439 Least integer k which, by a process analogous to the Keith numbers, reach k - n.
%H A377439 Paolo P. Lava, <a href="/A377439/b377439.txt">Table of n, a(n) for n = 0..1000</a>
%e A377439 a(6) = 11 because 1 + 1 = 2, 1 + 2 = 3, 2 + 3 = 5 that is 11 - 6.
%p A377439 with(numtheory): P:=proc(q, h) local a, b, c, j, k, n, t, v; v:=array(1..h); c:=[];
%p A377439 for j from 0 to 65 do for n from 10 to q do a:=n; b:=length(a);
%p A377439 for k from 1 to b do v[b-k+1]:=(a mod 10); a:=trunc(a/10); od; t:=b+1; v[t]:=add(v[k], k=1..b);
%p A377439 while v[t]<n-j do t:=t+1; v[t]:=add(v[k], k=t-b..t-1); od; if v[t]=n-j then c:=[op(c), n];
%p A377439 break;fi; od; od; op(c); end: P(10^6, 5000);
%Y A377439 Cf. A007629, A377416.
%K A377439 nonn,easy,base,changed
%O A377439 0,1
%A A377439 _Paolo P. Lava_, Oct 28 2024