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A213997
Number of integers between successive prime triples (p, p+2, p+6).
1
0, 0, 17, 53, 0, 77, 29, 77, 29, 107, 173, 173, 29, 17, 203, 179, 17, 119, 47, 0, 113, 257, 119, 77, 149, 23, 383, 23, 557, 203, 59, 137, 239, 77, 119, 383, 113, 143, 137, 29, 257, 239, 17, 143, 539, 623, 1043, 203, 137, 53, 239, 317, 563, 23, 863, 89, 23, 707
OFFSET
1,3
COMMENTS
Property of this sequence: either a(n) is odd == 2 (mod 3), or a(n) =0.
EXAMPLE
a(3)= 17 because between the 3rd and 4th prime triples there are 17 integers: (17,19,23), 24, 25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40, (41,43,47).
MAPLE
A213997 := proc(n)
max(0, A022004(n+1)-A022004(n)-7) ;
end proc: # R. J. Mathar, Jul 11 2012
MATHEMATICA
Flatten[Differences/@Table[Take[Flatten[Select[Partition[Prime[ Range[ 2000]], 3, 1], Differences[#]=={2, 4}&]], {3n, 3n+1}], {n, 60}]]-1/.{-1->0} (* Harvey P. Dale, Jun 10 2014 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Michel Lagneau, Jun 30 2012
STATUS
approved