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A198697
Values of local maxima in differences of primes, A001223.
2
4, 4, 6, 6, 6, 6, 8, 4, 14, 6, 10, 10, 4, 6, 10, 6, 14, 14, 10, 8, 8, 10, 10, 6, 8, 12, 8, 12, 18, 10, 10, 12, 12, 10, 10, 8, 8, 14, 12, 10, 4, 14, 14, 20, 10, 14, 8, 12, 6, 10, 10, 10, 18, 8, 22, 10, 10, 12, 12, 18, 6, 6, 12, 34, 18, 14, 8, 12, 4, 12, 8, 8
OFFSET
1,1
MAPLE
P:= select(isprime, [2, seq(i, i=3..1000, 2)]):
DP:= P[2..-1] - P[1..-2]:
J:= select(t -> DP[t] > DP[t-1] and DP[t] > DP[t+1], [$2..nops(DP)-1]):
DP[J]; # Robert Israel, Mar 07 2024
MATHEMATICA
nn = 1001; t = Differences[Prime[Range[nn]]]; t2 = {}; Do[If[t[[n - 1]] < t[[n]] && t[[n]] > t[[n + 1]], AppendTo[t2, {n, t[[n]]}]], {n, 2, nn - 2}]; Transpose[t2][[2]] (* T. D. Noe, Dec 27 2011 *)
Select[Partition[Differences[Prime[Range[400]]], 3, 1], #[[1]]<#[[2]]>#[[3]]&][[;; , 2]] (* Harvey P. Dale, Mar 07 2023 *)
CROSSREFS
Cf. A198696 (positions of local maxima in A001223).
Cf. A196175 (positions of local minima in A001223).
Cf. A001223 (first differences of primes).
Sequence in context: A019559 A365198 A274636 * A111657 A049751 A196594
KEYWORD
nonn
AUTHOR
Zak Seidov, Oct 29 2011
STATUS
approved