A066895 Numbers k such that k divides prime(k) + prime(k+1).

1, 2, 3, 6, 10, 16, 30, 120, 182, 439, 1058, 4122, 25356, 40086, 40090, 40114, 40120, 63416, 100347, 159222, 251708, 399930, 637328, 637336, 637340, 1014636, 2582486, 4124468, 6592708, 6592728, 10553440, 10553445, 10553829, 16899052, 27067138, 179992932

Offset: 1

Author

Benoit Cloitre, Jan 24 2002

Keywords

• nonn

Comments

Larger terms computed with the help of Kim Walisch's primecount. a(69) > 5*10^14. - Giovanni Resta, Jul 14 2018

Links

• Giovanni Resta, Table of n, a(n) for n = 1..68

Programs

Magma

S:=[]; p:=2; q:=p; for n in [1..10^7] do q:=NextPrime(q); if (p+q) mod n eq 0 then Append(~S, n); end if; p:=q; end for; S; // Klaus Brockhaus, Dec 28 2010

Mathematica

Select[Range[10^5], Mod[Prime[#] + Prime[# + 1], #] == 0 &] (* Giovanni Resta, Jul 14 2018 *)

PARI

{a=2;b=2;for(n=1,10^6,b=nextprime(b+1);(a+b)%n==0&print(n);a=b)} \\ Zak Seidov, Dec 28 2010

Extensions

Additional terms provided by Harvey P. Dale, Jan 28 2002

More terms from David W. Wilson, Feb 20 2002

Merged with an entry submitted by Zak Seidov, Dec 28 2010

a(35)-a(36) from Giovanni Resta, Jul 14 2018