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.

A277995 Primes with prime subscripts whose digits are primes, whose digital root is prime, whose sum of digits is prime and whose reversal is also prime.

Original entry on oeis.org

3, 5, 353, 32732237, 35225327, 75527537, 75535277, 75557723, 75737723, 75755257, 77322233, 77752733, 322375577, 322775737, 325725577, 325773727, 337735553, 352272233, 355322777, 357333377, 357735773, 372577727, 372753727, 375577733, 375722377, 375727237, 377725723, 377752723
Offset: 1

Views

Author

Ilya Gutkovskiy, Nov 08 2016

Keywords

Comments

Intersection of A006450, A007500, A019546, A028834 and A078403.

Examples

			32732237 is in the sequence because 32732237 is the 2016197-th prime number, 2016197 is prime, digits 2, 3 and 7 are primes, 32732237 -> 3 + 2 + 7 + 3 + 2 + 2 + 3 + 7 = 29 (is prime) -> 2 + 9 = 11 -> 1 + 1 = 2, 2 is prime and 73223723 is also prime.
		

Crossrefs

Programs

  • Mathematica
    Select[Table[Prime[Prime[n]], {n, 1500000}], Complement[IntegerDigits[#1], {2, 3, 5, 7}] == {} && PrimeQ[#1 - 9 Floor[(#1 - 1)/9]] && PrimeQ[Total[IntegerDigits[#1]]] && PrimeQ[FromDigits[Reverse[IntegerDigits[#1]]]] & ]