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A176601
Primes p that p//13 and p//31 are consecutive primes.
2
19, 853, 2287, 2467, 4243, 4513, 4621, 5431, 5701, 7243, 7477, 7591, 7927, 8221, 8317, 9283, 9439, 9817, 10039, 12781, 13933, 14461, 14923, 15727, 16693, 17443, 18199, 18217, 19207, 20749, 21139, 22147, 23761, 25471, 26701, 26953, 27481, 28111, 28447, 28579
OFFSET
1,1
COMMENTS
LINKS
EXAMPLE
19//13 = 1913 = prime(293), 19//31 = 1931 = prime(294), 19 = prime(8) is 1st term
853//13 = 85313 = prime(8306), 853//31 = 85331 = prime(8307), 853 = prime(147) is 2nd term
MATHEMATICA
okQ[n_]:=Module[{idn=IntegerDigits[n], p13, p31}, p13=FromDigits[ Join[ idn, {1, 3}]]; p31=FromDigits[Join[idn, {3, 1}]]; PrimeQ[p13]&&NextPrime[p13] == p31]; Select[Prime[Range[16000]], okQ] (* Harvey P. Dale, Jan 21 2012 *)
KEYWORD
base,nonn
AUTHOR
Eva-Maria Zschorn (e-m.zschorn(AT)zaschendorf.km3.de), Apr 21 2010
EXTENSIONS
More terms from Harvey P. Dale, Jan 21 2012
STATUS
approved