Fibonacci index
Find the index above 100 which is prime, whose reverse is prime, and for which the reverse of the Fibonacci number is prime.
Details
Example: Fibonacci [17] = 1597 where the index 17 is prime as well its reverse 71, and the number 1597 is prime as well its reverse 7951 which is also prime.
The answer is 191.
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1 solution
Fibonacci[191] = 3691087032412706639440686994833808526209 where both (index and the number) are prime and their palindromes are also primes. The only way to solve this problem is to find all prime Fibonacci numbers whose index above 100 are also primes and test their palindromes. The index (3 digits) above 100 which are primes are: 191 and 653 and the resulting Fibonacci number are also prime. The only one where the index and the number (both prime) have a prime palindrome prime is index 191.