A078847 Initial term in sequence of four consecutive primes separated by 3 consecutive differences each <= 6 (i.e., when d = 2, 4 or 6) and forming pattern = [2, 4, 6]; short notation = [246] d-pattern.
17, 41, 227, 347, 641, 1091, 1277, 1427, 1487, 1607, 2687, 3527, 3917, 4001, 4127, 4637, 4787, 4931, 8231, 9461, 10331, 11777, 12107, 13901, 14627, 20747, 21557, 23741, 25577, 26681, 26711, 27737, 27941, 28277, 29021, 31247, 32057, 32297
Offset: 1
Keywords
Examples
17, 17+2 = 19, 17+2+4 = 23, 17+2+4+6 = 29 are consecutive primes.
Links
- Zak Seidov, Table of n, a(n) for n = 1..2000
Crossrefs
Cf. analogous prime quadruple sequences with various possible {2, 4, 6}-difference-patterns in brackets: A007530[242], A078847[246], A078848[264], A078849[266], A052378[424], A078850[426], A078851[462], A078852[466], A078853[624], A078854[626], A078855[642], A078856[646], A078857[662], A078858[664], A033451[666].
Programs
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Mathematica
d = Differences[Prime[Range[10000]]]; Prime[Flatten[Position[Partition[d, 3, 1], {2, 4, 6}]]] (* T. D. Noe, May 23 2011 *) Transpose[Select[Partition[Prime[Range[10000]],4,1],Differences[#] == {2,4,6}&]][[1]] (* Harvey P. Dale, Aug 07 2013 *)
Formula
Primes p=prime(i) such that prime(i+1) = p+2, prime(i+2) = p+2+4, prime(i+3) = p+2+4+6.
Extensions
Listed terms verified by Ray Chandler, Apr 20 2009
Additional cross references from Harvey P. Dale, May 10 2014
Comments