A253973 Primes p such that p + nextprime(p) is divisible by 9.

7, 17, 43, 71, 79, 97, 107, 139, 179, 197, 223, 269, 277, 283, 313, 317, 337, 349, 401, 409, 431, 439, 457, 491, 521, 673, 743, 761, 787, 809, 827, 839, 853, 881, 907, 1021, 1039, 1061, 1087, 1151, 1193, 1213, 1277, 1303, 1373, 1399, 1429, 1447, 1471, 1483

Offset: 1

Author

Vincenzo Librandi, Jan 28 2015

Keywords

• nonn
• easy

Examples

			p=43 is in this sequence because 43+47 = 90 is divisible by 9.
		

Links

• Harvey P. Dale, Table of n, a(n) for n = 1..1000

Crossrefs

Cf. similar sequences listed in A253969.

Programs

Magma

[p: p in PrimesUpTo(1500) | (p+NextPrime(p)) mod 9 eq 0];

Mathematica

Prime@Select[Range[300], Mod[Prime[#] + Prime[# + 1], 9]==0 &]
Select[Partition[Prime[Range[300]],2,1],Divisible[Total[#],9]&][[All,1]] (* Harvey P. Dale, Jul 27 2017 *)

PARI

forprime(p=1,10^3,if(!((p+nextprime(p+1))%9),print1(p,", "))) \\ Derek Orr, Jan 30 2015