cp's OEIS Frontend

A282839 Numbers that are equal to the sum of descending numbers raised to their digits' powers.

%I A282839 #23 Feb 18 2021 01:36:31
%S A282839 1,65,6796
%N A282839 Numbers that are equal to the sum of descending numbers raised to their digits' powers.
%C A282839 Sequence is complete.
%e A282839 1 = 1^1;
%e A282839 65 = 2^6 + 1^5;
%e A282839 6796 = 4^6 + 3^7 + 2^9 + 1^6.
%t A282839 Select[Range[10^5], # == Total[ Reverse[ Range@ IntegerLength@ #]^ IntegerDigits@ #] &] (* _Giovanni Resta_, Feb 23 2017 *)
%o A282839 (VBA)
%o A282839 sub calcul()
%o A282839 sheets("Result").select
%o A282839 range("A1").select
%o A282839 for i=1 to 10^13
%o A282839 sum=0
%o A282839 for k=1 to len(i)
%o A282839 sum=sum+(len(i)-k+1)^mid(i,k,1)
%o A282839 next
%o A282839 if i=sum then
%o A282839 activecell.value=i
%o A282839 activesheet.offset(1,0).select
%o A282839 end if
%o A282839 next
%o A282839 end sub
%o A282839 (PARI) isok(n) = my(d=digits(n)); sum(k=1, #d, (#d-k+1)^d[k]) == n; \\ _Michel Marcus_, Feb 24 2017
%Y A282839 Cf. A035138, A032799.
%K A282839 nonn,base,bref,fini,full
%O A282839 1,2
%A A282839 _Shmelev Aleksei_, Feb 22 2017