Octagonal numbers are defined and calculated by this extraordinary intricate and excruciatingly complex formula. So, this line is for experts only _{}
base x ( 3 x base - 2 )
A palindromic octagonal numbers can only end with digit 1, 3, 5, 6 and 8.
Exhaustive search performed upto length 37 by Patrick De Geest Higher values up to length 43 were found and submitted by Feng Yuan.
Feng Yuan (email) from Washington State, USA, discovered the palindromic octagonals with index numbers 31 & 32 [ January 3, 2008 ].
Feng Yuan (email) from Washington State, USA, discovered the palindromic octagonals starting from index number 17 up to 30.
The Lowell Family (email) submitted the first 7 palindromic octagonals.
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