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A357143 a(n) is sum of the base-5 digits of n each raised to the number of digits of n in base 5.

%I A357143 #63 Oct 26 2023 20:17:21
%S A357143 1,2,3,4,1,2,5,10,17,4,5,8,13,20,9,10,13,18,25,16,17,20,25,32,1,2,9,
%T A357143 28,65,2,3,10,29,66,9,10,17,36,73,28,29,36,55,92,65,66,73,92,129,8,9,
%U A357143 16,35,72,9,10,17,36,73,16,17,24,43,80,35,36,43,62,99,72,73,80,99,136,27
%N A357143 a(n) is sum of the base-5 digits of n each raised to the number of digits of n in base 5.
%H A357143 Robert Israel, <a href="/A357143/b357143.txt">Table of n, a(n) for n = 1..10000</a>
%F A357143 a(n) = Sum_{i=1..A110592(n)} d(i)^A110592(n), where d(i) is the i-th digit of n in base 5.
%e A357143 For n = 13_10 = 23_5 (2 digits in base 5): a(13) = 2^2 + 3^2 = 13.
%e A357143 For n = 73_10 = 243_5 (3 digits in base 5): a(73) = 2^3 + 4^3 + 3^3 = 99.
%p A357143 f:= proc(n) local L,d,i;
%p A357143   L:= convert(n,base,5);
%p A357143   d:= nops(L);
%p A357143   add(L[i]^d,i=1..d)
%p A357143 end proc:
%p A357143 map(f,[$1..100]); # _Robert Israel_, Oct 26 2023
%t A357143 a[n_] := Total[IntegerDigits[n, 5]^IntegerLength[n, 5]]; Array[a, 100] (* _Amiram Eldar_, Oct 30 2022 *)
%o A357143 (PARI) a(n) = my(d=digits(n, 5)); sum(k=1, #d, d[k]^#d); \\ _Michel Marcus_, Oct 29 2022
%o A357143 (Python)
%o A357143 from sympy.ntheory.factor_ import digits
%o A357143 def A357143(n):
%o A357143     t = len(s:=digits(n,5)[1:])
%o A357143     return sum(d**t for d in s) # _Chai Wah Wu_, Oct 31 2022
%Y A357143 Cf. A357954, A010346, A110592.
%Y A357143 Cf. in base 10: A157714, A101337, A151544.
%K A357143 nonn,base
%O A357143 1,2
%A A357143 _Francesco A. Catalanotti_, Oct 26 2022
%E A357143 Corrected and extended by _Michel Marcus_, Oct 29 2022