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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 (list; graph; refs; listen; history; text; internal format)
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.

LINKS

Table of n, a(n) for n=1..5.

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

Adjacent sequences:  A246554 A246555 A246556 * A246558 A246559 A246560

KEYWORD

nonn,fini,full,base

AUTHOR

Michel Lagneau, Nov 15 2014

STATUS

approved

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Last modified January 21 07:12 EST 2022. Contains 350473 sequences. (Running on oeis4.)