A237575 - OEIS

%I #17 Aug 31 2022 16:01:06

%S 0,1,1,2,3,5,8,31,93,421,541,962,5310,7622,93221,843100,963321,

%T 8642110,9654310,98642210,986522100,8654311100,9864332000,88654311100,

%U 98865431100,987754221100,9866652211000,86544432110000,98644321110000,888755322110000

%N Fibonacci-like numbers with nonincreasing positive digits. Let a** denote the number that is obtained from a if its digits are written in nonincreasing order. Let a<+>b = (a + b)**. a(0)=0, a(1)=1, for n>=2,  a(n) = a(n-1) <+> a(n-2).

%H Peter J. C. Moses, <a href="/A237575/b237575.txt">Table of n, a(n) for n = 0..499</a>

%p a:= proc(n) option remember; `if`(n<2, n, parse(cat(

%p       sort(convert(a(n-1)+a(n-2), base, 10), `>`)[])))

%p     end:

%p seq(a(n), n=0..30);  # _Alois P. Heinz_, Aug 31 2022

%t a[0]:=0;a[1]:=1;a[n_]:=a[n]=FromDigits[Reverse[Sort[IntegerDigits[a[n-1]+a[n-2]]]]];Map[a,Range[0,20]] (* _Peter J. C. Moses_, Feb 09 2014 *)

%Y Cf. A000045, A001129, A004185, A069638, A237568.

%K nonn,base

%O 0,4

%A _Vladimir Shevelev_, Feb 09 2014

%E Correction and extension by _Peter J. C. Moses_