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A358528
a(n) = n-th prime p(k) such that p(k) - p(k-1) > p(k-1) - p(k-2).
5
5, 11, 17, 23, 29, 37, 47, 53, 67, 79, 89, 97, 107, 113, 127, 137, 149, 157, 173, 191, 197, 211, 233, 239, 251, 277, 293, 307, 317, 331, 347, 353, 359, 367, 389, 397, 409, 419, 431, 439, 449, 457, 467, 479, 499, 509, 521, 541, 557, 577, 587, 607, 631, 647
OFFSET
1,1
COMMENTS
This sequence, together with A358530 and A181424, partition the set of primes >= 5. The corresponding sequences of indices, A358529, A358531, and A356347, partition the set of positive integers >= 3.
EXAMPLE
n 1 2 3 4 5 6 7
k 3 5 7 9 10 12 15
p(n) 5 11 17 23 29 37 47
MATHEMATICA
t = Select[2 + Range[140],
Prime[#] - Prime[# - 1] > Prime[# - 1] - Prime[# - 2] &] (* A358529 *)
Prime[t] (* A358528 *)
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Clark Kimberling, Nov 21 2022
STATUS
approved