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A341763 Numbers whose trajectory under iteration of sum of cubes of digits (map) produce a narcissistic number greater than nine.

%I A341763 #15 Mar 20 2021 14:40:10
%S A341763 2,3,5,6,7,8,9,11,12,14,15,17,18,19,20,21,23,24,26,27,29,30,32,33,34,
%T A341763 35,36,37,38,39,41,42,43,44,45,47,48,50,51,53,54,56,57,58,59,60,62,63,
%U A341763 65,66,67,68,69,70,71,72,73,74,75,76,77,78,80,81,83,84,85
%N A341763 Numbers whose trajectory under iteration of sum of cubes of digits (map) produce a narcissistic number greater than nine.
%C A341763 Conjecture: all multiples of 3 are terms of this sequence.
%H A341763 J. J. Camacho, <a href="https://www.masscience.com/2020/06/16/un-metodo-insospechado-para-encontrar-numeros-narcisistas/">Un Método Insospechado Para Encontrar Números Narcisistas</a> (in Spanish)
%e A341763 For a(1) = 2:
%e A341763 2^3 = 8.
%e A341763 8^3 = 512.
%e A341763 5^3 + 1^3 + 2^3 = 134.
%e A341763 1^3 + 3^3 + 4^3 = 92.
%e A341763 9^3 + 2^3 = 737.
%e A341763 7^3 + 3^3 + 7^3 = 713.
%e A341763 7^3 + 1^3 + 3^3 = 371.
%e A341763 371 is a narcissistic number.
%t A341763 (* A example with recurrence formula to test if the number belongs to this sequence *)
%t A341763 f[1] = 2;
%t A341763 f[n_] := Total[IntegerDigits[f[n - 1]]^3]
%t A341763 Table[Total[IntegerDigits[f[n]]^3], {n, 1, 10}]
%Y A341763 Cf. A055012 (sum of cubes of digits), A005188 (narcissistic numbers).
%K A341763 nonn,base
%O A341763 1,1
%A A341763 _José de Jesús Camacho Medina_, Feb 19 2021