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A227508
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Numbers n such that n! is divisible by R(n), the digit reversal of n.
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1
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1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 18, 19, 20, 21, 22, 23, 24, 25, 27, 29, 30, 31, 32, 33, 36, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78
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OFFSET
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1,2
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COMMENTS
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LINKS
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EXAMPLE
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12 is a member since R(12)=21 divides 12! while 13 is not a member as 31 does not divide 13!.
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MAPLE
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read("transforms"):
isA227508 := proc(n)
if modp(n!, digrev(n)) = 0 then
true;
else
false ;
end if;
end proc:
if n = 1 then
1;
else
for a from procname(n-1)+1 do
if isA227508(a) then
return a;
end if;
end do:
end if;
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MATHEMATICA
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Select[Range[79], Divisible[#!, FromDigits[Reverse[IntegerDigits[#]]]] &]
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CROSSREFS
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KEYWORD
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nonn,base
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AUTHOR
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STATUS
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approved
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