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%I #22 May 28 2020 10:32:46
%S 0,1,48,240,407,5920,5921,2918379,7444416,18125436,210897052,
%T 6303187514,8948360198,10462450356,11647261846,18107015789,
%U 27434621679,31332052290,4986706842391,485927682264092,1287253463537089,126835771455251081,559018292730428520,559018292730428521
%N Numbers m such that m equals abs(d_1^k - d_2^k + d_3^k - d_4^k ...), where d_i is the decimal expansion of m and k is some power greater than 2.
%C For terms > 1, the exponents k are 2, 4, 3, 4, 4, 7, 8, 8, 11, 11, 21, 11, 11, 11, 11, 13, 15, 16, 22, 21, 21.
%e 48 = abs(4^2 - 8^2), 5920 = abs(5^4 - 9^4 + 2^4 - 0^4).
%o (Python)
%o def moda(n,a)
%o kk,j = 0,1
%o while n > 0:
%o kk= kk-j*(n%10)**a
%o n,j =int(n//10),-j
%o return abs(kk)
%o for i in range (0,10**12):
%o for t in range(2,21):
%o if i==moda(i,t):
%o print (i,t,moda(i,t))
%Y Cf. A005188, A007770, A023052.
%K nonn,base
%O 1,3
%A _Pieter Post_, Apr 01 2020
%E a(19)-a(24) from _Giovanni Resta_, Apr 02 2020