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%I A284812 #14 Apr 10 2017 12:34:13
%S A284812 4,34,78,47863,67277,472621,525038,5576423,7541551,12485411,13600033,
%T A284812 41777431,48288701,64979641,97807441,136272511,153060223,201916441,
%U A284812 214821521,225015223
%N A284812 Numbers n such that n' = d_1^1 + d_2^2 + ... + d_k^k where d_1, d_2, ..., d_k are the digits of n, with MSD(n) = d_1 and LSD(n) = d_k, and n' is the arithmetic derivative of n.
%e A284812 47863' = 2104 = 4^1 + 7^2 + 8^3 + 6^4 + 3^5.
%p A284812 with(numtheory): P:=proc(q) local a,k,n,p; for n from 1 to q do a:=convert(n,base,10);
%p A284812 if add(a[k]^(nops(a)-k+1),k=1..nops(a))=n*add(op(2,p)/op(1,p),p=ifactors(n)[2])
%p A284812 then print(n); fi; od; end: P(10^9);
%Y A284812 Cf. A003415, A284213.
%K A284812 nonn,base,more
%O A284812 1,1
%A A284812 _Paolo P. Lava_, Apr 07 2017

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