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A282839
Numbers that are equal to the sum of descending numbers raised to their digits' powers.
0
OFFSET
1,2
COMMENTS
Sequence is complete.
EXAMPLE
1 = 1^1;
65 = 2^6 + 1^5;
6796 = 4^6 + 3^7 + 2^9 + 1^6.
MATHEMATICA
Select[Range[10^5], # == Total[ Reverse[ Range@ IntegerLength@ #]^ IntegerDigits@ #] &] (* Giovanni Resta, Feb 23 2017 *)
PROG
(VBA)
sub calcul()
sheets("Result").select
range("A1").select
for i=1 to 10^13
sum=0
for k=1 to len(i)
sum=sum+(len(i)-k+1)^mid(i, k, 1)
next
if i=sum then
activecell.value=i
activesheet.offset(1, 0).select
end if
next
end sub
(PARI) isok(n) = my(d=digits(n)); sum(k=1, #d, (#d-k+1)^d[k]) == n; \\ Michel Marcus, Feb 24 2017
CROSSREFS
Sequence in context: A116104 A116121 A118707 * A144661 A296144 A373761
KEYWORD
nonn,base,bref,fini,full
AUTHOR
Shmelev Aleksei, Feb 22 2017
STATUS
approved