cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A345956 Primes whose reverse is the square of a Fibonacci number.

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%I A345956 #18 Jul 03 2021 16:05:43
%S A345956 1297,921241,186331288599111530713519,
%T A345956 98866853184420632874393761586063024530467395043
%N A345956 Primes whose reverse is the square of a Fibonacci number.
%e A345956 The reverse of 1297 is 7921 = 89^2, where 89 is a Fibonacci number. Thus 1297 is in this sequence.
%t A345956 Select[IntegerReverse/@(Fibonacci@Range@1000^2),PrimeQ] (* _Giorgos Kalogeropoulos_, Jun 30 2021 *)
%o A345956 (PARI) for(k=3,200,my(f=fibonacci(k)^2,fi=fromdigits(Vecrev(digits(f))));if(isprime(fi),print1(fi,", "))) \\ _Hugo Pfoertner_, Jun 30 2021
%o A345956 (Python)
%o A345956 from sympy import fibonacci, isprime
%o A345956 def rev(n): return int(str(n)[::-1])
%o A345956 def auptok(klimit): return [t for t in (rev(fibonacci(k)**2) for k in range(3, klimit+1)) if isprime(t)]
%o A345956 print(auptok(200)) # _Michael S. Branicky_, Jun 30 2021
%Y A345956 Cf. A007488 (primes whose reversal is a square), A036797 (Iccanobif primes).
%Y A345956 Cf. A000045, A007598.
%K A345956 nonn,base
%O A345956 1,1
%A A345956 _Tanya Khovanova_, Jun 30 2021