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A174042
Places n for which A046132(n) and A006512(n) is a twin prime pair.
1
1, 9, 10, 24, 28, 67, 195, 361, 362, 382, 459, 462, 470, 759, 765, 766, 794, 864, 869, 909, 1189, 1300, 1303, 1374, 1378, 1642, 1657, 1659, 3727, 3755, 4187, 4368, 4413, 4677, 4684, 4721, 4927, 4945, 5221, 5270, 5313, 5409, 5627, 5945, 7587, 7588, 7789
OFFSET
1,2
EXAMPLE
1 is in the sequence because A046132(1)=7 and A006512(1)=5 are twin primes.
MAPLE
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:
A046132 := proc(n) 4+A023200(n) ; end proc:
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:
A006512 := proc(n) 2+A001359(n) ; end proc:
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
CROSSREFS
Sequence in context: A309485 A228378 A326464 * A263261 A290275 A156787
KEYWORD
nonn
AUTHOR
Vladimir Shevelev, Mar 06 2010
EXTENSIONS
Extended beyond 28 by R. J. Mathar, Nov 03 2011
More terms from Michel Marcus, Dec 19 2018
STATUS
approved