A138122 - OEIS

A138122

Cousin primes, the lower of which is 7 (mod 10).

7, 11, 37, 41, 67, 71, 97, 101, 127, 131, 277, 281, 307, 311, 397, 401, 457, 461, 487, 491, 757, 761, 877, 881, 907, 911, 937, 941, 967, 971, 1087, 1091, 1297, 1301, 1447, 1451, 1567, 1571, 1597, 1601, 1867, 1871, 2137, 2141, 2347, 2351, 2377, 2381, 2437

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OFFSET

1,1

COMMENTS

Start from the intersection of A023200 and A030432, then add the associated members of A046132. The last digits are obviously periodic as A010688. - R. J. Mathar, Nov 26 2008

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 1..1000

MATHEMATICA

a[0] = 7; a[n_] := a[n] = a[n - 1] + 10; Flatten[Table[If[PrimeQ[a[n]] && PrimeQ[a[n] + 4], {a[n], a[n] + 4}, {}], {n, 0, 1000}]]

CROSSREFS

Cf. A132243, A132242, A076746.

Sequence in context: A241573 A215442 A019416 * A176955 A227281 A268579

Adjacent sequences: A138119 A138120 A138121 * A138123 A138124 A138125

KEYWORD

nonn

AUTHOR

Roger L. Bagula, May 04 2008

EXTENSIONS

Replaced Mathematica definition by humanly readable phrase. - R. J. Mathar, Nov 26 2008

STATUS

approved