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A158328 Lessers p1 of twin primes with prime sums of digits of p1 and p2. 1
3, 5, 41, 137, 191, 197, 227, 281, 311, 461, 599, 641, 821, 827, 881, 1031, 1091, 1277, 1301, 1451, 1721, 1871, 2027, 2081, 2087, 2111, 2267, 2591, 2711, 2801, 3167, 3251, 3257, 3299, 3527, 3581, 3671, 3851, 4001, 4157, 4241, 4337, 4421, 4481, 4517, 4799 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Or, numbers n such that n and n+2 are terms in A046704. [Zak Seidov, Feb 02 2010]

LINKS

Robert Israel, Table of n, a(n) for n = 1..10000

EXAMPLE

a(3)=41 is in the sequence because 41, 41+2=43, 4+1=5 and 4+3=7 are primes.

a(4)=137 is in the sequence because 137, 137+2=139, 1+3+7=11 and 1+3+9=13 are primes.

MAPLE

sd:= n -> convert(convert(n, base, 10), `+`):

p:= 1: q:= 2: count:= 0: Res:= NULL:

while count < 100 do

  if q = p+2 and isprime(sd(p)) and isprime(sd(q)) then

      count:= count+1; Res:= Res, p

  fi;

  p:= q; q:= nextprime(q);

od:

Res; # Robert Israel, Apr 08 2018

MATHEMATICA

sd[n_]:=Plus@@IntegerDigits[n]; Select[Prime[Range[650]], And@@PrimeQ[{#+2, sd[#], sd[#+2]}] &] (* Jayanta Basu, May 25 2013 *)

CROSSREFS

Cf. A001359, A046704.

Sequence in context: A145912 A096058 A120265 * A258933 A060433 A216085

Adjacent sequences:  A158325 A158326 A158327 * A158329 A158330 A158331

KEYWORD

nonn,base

AUTHOR

Juri-Stepan Gerasimov, Mar 16 2009

EXTENSIONS

Corrected by Juri-Stepan Gerasimov, Mar 24 2009

3299 and 4481 inserted by R. J. Mathar, Mar 27 2009

Example edited by Robert Israel, Apr 08 2018

STATUS

approved

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Last modified April 3 13:32 EDT 2020. Contains 333197 sequences. (Running on oeis4.)