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A246557
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.
0
116955, 125000, 228177, 375000, 495248
OFFSET
1,1
COMMENTS
The sequence is finite.
If the number of digits of n is odd then the analogous product can never equal n.
EXAMPLE
116955 is in the sequence because we get 1695 and then 69, whose product is 116955.
MAPLE
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):
CROSSREFS
Sequence in context: A156417 A156865 A233681 * A289911 A206204 A251953
KEYWORD
nonn,fini,full,base
AUTHOR
Michel Lagneau, Nov 15 2014
STATUS
approved