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
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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