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A080377
Prime gaps where A080374 increases.
0
2, 4, 6, 8, 14, 10, 18, 22, 34, 16, 26, 32, 38, 50, 62, 54, 58, 46, 64, 86, 82, 74, 98, 106, 94, 118, 122, 128, 146, 134, 142, 162, 178, 158, 166, 202, 194, 206, 214, 218, 242, 250, 226, 254, 274, 262, 256, 278, 326, 302, 298, 314, 382, 346, 358, 338, 394, 334, 386, 362, 398, 446, 454, 486
OFFSET
1,1
COMMENTS
a(n+1) is the smallest prime gap (A001223) that has a prime factor not present in previous gaps or was present but at a lower power.
FORMULA
a(n) = prime(1+A080376(n)) - prime(A080376(n)).
EXAMPLE
18 is the 7th term: in the first 6 terms, {2, 4, 6, 8, 14, 10}, 3 does not occur with power 2 unlike in 18 = 2 * 3^2.
22 is the 8th term: in the first 7 terms 11 is not a prime factor unlike 22.
Several even numbers do not arise in this sequence, e.g., 12, 20, 36, 48, etc..
MATHEMATICA
s=1; Do[s1=s; s=LCM[s, d=Prime[n+1]-Prime[n]]; If[Greater[s, s1], Print[d]], {n, 1, 10000000}]
CROSSREFS
KEYWORD
nonn
AUTHOR
Labos Elemer, Feb 27 2003
EXTENSIONS
More terms from Amiram Eldar, Feb 09 2025
STATUS
approved