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A246557
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Numbers n with an even number of digits such that the product of the numbers formed by successively deleting pairs of digits from the ends of n is equal to n.
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0
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OFFSET
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1,1
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COMMENTS
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The sequence is finite.
If the number of digits of n is odd then the analogous product can never equal n.
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LINKS
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EXAMPLE
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116955 is in the sequence because we get 1695 and then 69, whose product is 116955.
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MAPLE
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lst:={}:
for a from 1 to 99 do:
for b from 1 to 9 do:
for c from 0 to 9 do:
x1:=a*10+c:x:=b*10^length(x1)+x1:
z:=a*x:l:=length(z) :
u:=(z-irem(z, 10))/10: v0:=irem(u, 10^(l-2)):
if v0 = x then lst:=lst union {z}:
else
fi:
od:
od:
od:
print(lst):
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CROSSREFS
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KEYWORD
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nonn,fini,full,base
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AUTHOR
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STATUS
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approved
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