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Places n for which A046132(n) and A006512(n) is a twin prime pair.
1

%I #9 Dec 19 2018 15:06:51

%S 1,9,10,24,28,67,195,361,362,382,459,462,470,759,765,766,794,864,869,

%T 909,1189,1300,1303,1374,1378,1642,1657,1659,3727,3755,4187,4368,4413,

%U 4677,4684,4721,4927,4945,5221,5270,5313,5409,5627,5945,7587,7588,7789

%N Places n for which A046132(n) and A006512(n) is a twin prime pair.

%e 1 is in the sequence because A046132(1)=7 and A006512(1)=5 are twin primes.

%p A023200 := proc(n) option remember; if n = 1 then 3; else p := nextprime(procname(n-1)) ; while not isprime(p+4) do p := nextprime(p) ; end do: p ; end if; end proc:

%p A046132 := proc(n) 4+A023200(n) ; end proc:

%p A001359 := proc(n) option remember; if n = 1 then 3; else p := nextprime(procname(n-1)) ; while not isprime(p+2) do p := nextprime(p) ; end do: p ; end if; end proc:

%p A006512 := proc(n) 2+A001359(n) ; end proc:

%p for n from 1 do if A046132(n)+2 = A006512(n) or A046132(n) = A006512(n)+2 then printf("%d,\n",n); end if; end do: # _R. J. Mathar_, Nov 03 2011

%Y Cf. A006512, A046132.

%K nonn

%O 1,2

%A _Vladimir Shevelev_, Mar 06 2010

%E Extended beyond 28 by _R. J. Mathar_, Nov 03 2011

%E More terms from _Michel Marcus_, Dec 19 2018