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A193419 Numbers n such that 4n+3 is a palindromic prime. 0
0, 1, 2, 32, 37, 47, 95, 181, 196, 229, 2827, 2852, 3332, 3457, 3482, 3862, 3887, 4367, 4492, 4847, 4972, 4997, 7525, 7550, 7600, 7675, 7700, 8080, 8105, 8635, 8710, 9065, 9140, 9520, 9545, 9695, 17551, 17626, 17651, 18056, 18181, 18511, 18686, 19091, 19166 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

The subsequence of primes p such that 4p+3 is a palindromic prime begins: 2, 37, 47, 181, 229, 3457.

LINKS

Table of n, a(n) for n=1..45.

FORMULA

{n such that A004767(n) is in A002385}.

EXAMPLE

a(1) = 2 because 4*2 + 3 = 11, and R(11) = 11 is prime.

a(2) = 37 because 4*37 + 3 = 151 is prime, and R(151) = 151.

MATHEMATICA

ppQ[n_]:=Module[{c=4n+3, d}, d=IntegerDigits[c]; PrimeQ[c]&&d == Reverse[ d]]; Select[Range[0, 20000], ppQ] (* Harvey P. Dale, Aug 02 2011 *)

CROSSREFS

Cf. A000040, A002385, A004767, A004086, A192261.

Sequence in context: A004842 A022378 A306950 * A160557 A103028 A139732

Adjacent sequences:  A193416 A193417 A193418 * A193420 A193421 A193422

KEYWORD

nonn,easy,base

AUTHOR

Jonathan Vos Post, Jul 26 2011

STATUS

approved

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Last modified August 26 01:47 EDT 2019. Contains 326324 sequences. (Running on oeis4.)