A198697 Values of local maxima in differences of primes, A001223.

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

Links

Robert Israel, Table of n, a(n) for n = 1..10000

Zak Seidov, A001223: maxima of 2nd order

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

Adjacent sequences: A198694 A198695 A198696 * A198698 A198699 A198700

Keyword

nonn

Author

Zak Seidov, Oct 29 2011

Status

approved