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A118134
Primes p such that 4p is the sum of two consecutive primes.
12
2, 3, 13, 17, 43, 67, 127, 137, 167, 193, 223, 283, 487, 563, 613, 617, 643, 647, 773, 1033, 1187, 1193, 1277, 1427, 1453, 1483, 1543, 1663, 1847, 1949, 2027, 2143, 2297, 2371, 2423, 2437, 2477, 2503, 2609, 2683, 2843, 2857, 2927, 3119, 3137, 3163, 3253, 3433
OFFSET
1,1
COMMENTS
From Zak Seidov, Jun 18 2016: (Start)
Minimal difference between odd terms is 4.
a(n+1) - a(n) = 4 for n = {3, 15, 17, 147, 209, 277, 414, 422, 495, 825, 1053, 1380, 1504, 2078, 2264, 2375, 2605, 4224, 4495, 5180, 5825, 6497, 7107, 7372, 8951} and a(n) = {13, 613, 643, 16183, 24763, 37993, 63853, 65323, 81703, 154153, 210853, 295873, 327823, 479023, 537583, 568903, 632323, 1111723, 1195543, 1415833, 1626433, 1853443, 2060503, 2146813, 2702893} == 13 mod 30. (End)
LINKS
Charles R Greathouse IV, Table of n, a(n) for n = 1..10000
EXAMPLE
13 is there because it is prime and 4*13 = 23+29.
MATHEMATICA
pr = Prime[Range[1000]]; Select[(Total /@ Partition[pr, 2, 1])/4, PrimeQ] (* Zak Seidov, Jun 29 2017 *)
PROG
(PARI) is(n)=isprime(n) && precprime(2*n)+nextprime(2*n)==4*n \\ Charles R Greathouse IV, Apr 24 2015
CROSSREFS
Cf. A001043 (sums of two consecutive primes).
Sequence in context: A215359 A115898 A215350 * A215386 A352539 A338216
KEYWORD
nonn
AUTHOR
Anton Vrba (antonvrba(AT)yahoo.com), May 13 2006
EXTENSIONS
Edited by Don Reble, Jul 23 2006
STATUS
approved