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A308125 Numbers k that are a multiple of the DENEAT operator applied to k (A073053).

%I A308125 #19 Aug 25 2021 06:58:36
%S A308125 0,22,44,66,88,123,264,369,462,615,660,738,759,852,957,1120,1344,1568,
%T A308125 1884,2024,2068,2200,2244,2288,2420,2464,2640,2684,2860,2912,3350,
%U A308125 3360,3584,3752,4004,4048,4224,4268,4400,4444,4488,4620,4664,4840,4884,5024,6028,6204
%N A308125 Numbers k that are a multiple of the DENEAT operator applied to k (A073053).
%C A308125 The DENEAT operator is also known as the Sisyphus function.
%C A308125 On the other hand, the sequence of numbers k such that DENEAT(k) is a multiple of k, is the finite sequence {1, 11, 14, 16, 22, 56, 123}.
%D A308125 J. Schram, The Sisyphus string, J. Rec. Math., 19:1 (1987), 43-44.
%H A308125 Paolo P. Lava, <a href="/A308125/b308125.txt">Table of n, a(n) for n = 0..1000</a>
%e A308125 2912 / DENEAT(2912) = 2912 / 224 = 13.
%p A308125 P:=proc(n) local a,b,c,d,k; a:=convert(n,base,10); b:=0: c:=0:
%p A308125 for k from 1 to nops(a) do if a[k] mod 2=0 then b:=b+1; else c:=c+1; fi;
%p A308125 od: d:=b*10^length(c)+c; a:=n/(d*10^length(length(n))+length(n)):
%p A308125 if frac(a)=0 then n; fi; end: 0,seq(P(i),i=1..6204);
%Y A308125 Cf. A073053, A073054.
%K A308125 nonn,base,easy
%O A308125 0,2
%A A308125 _Paolo P. Lava_, May 14 2019