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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.
0
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
1,1
COMMENTS
Intersection of A006450, A007500, A019546, A028834 and A078403.
EXAMPLE
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.
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]]]] & ]
KEYWORD
nonn,base
AUTHOR
Ilya Gutkovskiy, Nov 08 2016
STATUS
approved