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A279067
Least prime q such that (r-q)/(q-p), where p<q<r are three consecutive primes, produces a new ratio <= 1, arranged by Farey fractions A038566/A038567.
3
5, 11, 29, 37, 6421, 367, 149, 14281, 251, 701, 521, 631, 84913, 127, 331, 75479, 787, 7057, 1949, 3407, 388621, 1847, 1277, 1087, 2879, 1399, 13859, 4621, 43391, 1657, 743507, 40213, 1151, 162209, 1973, 3491, 736577, 2579, 8039, 1264129, 14369, 43691, 4547, 4201, 8147, 29101
OFFSET
1,1
COMMENTS
Almost a bisection of A275785 with only the term 5 being in both A279066 & A279067.
The union of A279066 & A279067 is A275785 with only 5 as a common term.
Records: 5, 11, 29, 37, 6421, 14281, 84913, 388621, 743507, 1264129, 1491377, 1613279, 15733451, 27196633, 106132883, 125747441, 304328911, 344278939, 756574061, 1166821769, 2691812749, ..., .
1/n = A179256(n).
LINKS
EXAMPLE
Row 1: 1/1 5
Row 2: 1/2 11
Row 3: 1/3 2/3 29 37
Row 4: 1/4 3/4 6421 367
Row 5: 1/5 2/5 3/5 4/5 149 14281 251
Row 6: 1/6 5/6 521 631
Row 7: 1/7 .. 6/7 84913 127 331 75479 787 7057
Row 8: 1/8 3/8 5/8 7/8 1949 3407 388621 1847
etc.
MATHEMATICA
f[n_] := Block[{p = 2, q = 3, r = 5}, While[(r - q) != n(q - p), p = q; q = r; r = NextPrime@ r]; q]; Farey[n_] := Union@ Flatten@ Table[a/b, {b, n}, {a, 0, b}]; ff = Rest@ Reverse@ Sort[ Farey[25], Denominator[#2] < Denominator[#1] &]; f@# & /@ ff
CROSSREFS
KEYWORD
nonn
AUTHOR
STATUS
approved