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A123080 Twin primes of form 4k+3. 0
3, 7, 11, 19, 31, 43, 59, 71, 103, 107, 139, 151, 179, 191, 199, 227, 239, 271, 283, 311, 347, 419, 431, 463, 523, 571, 599, 619, 643, 659, 811, 823, 827, 859, 883, 1019, 1031, 1051, 1063, 1091, 1151, 1231, 1279, 1291, 1303, 1319, 1427, 1451, 1483, 1487, 1607 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..51.

MAPLE

i:=1:for k from 1 to 3000 do if isprime(k) and isprime(k+2) then b:=k:c:=k+2: if b mod 4 = 3 then a[i]:=b:i:=i+1 fi: if c mod 4 = 3 then a[i]:=c:i:=i+1 fi:fi od: seq(a[n], n=1..i-1);

MATHEMATICA

Select[Flatten[Select[Partition[Prime[Range[260]], 2, 1], Last[#]-First[#] == 2&]], IntegerQ[(#-3)/4]&] (* Harvey P. Dale, Apr 20 2011 *)

CROSSREFS

Cf. A122564, A122565, A001097.

Sequence in context: A158722 A202301 A339974 * A161387 A229086 A354902

Adjacent sequences: A123077 A123078 A123079 * A123081 A123082 A123083

KEYWORD

nonn

AUTHOR

Miklos Kristof, Sep 27 2006

STATUS

approved

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Last modified January 27 21:49 EST 2023. Contains 359849 sequences. (Running on oeis4.)