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A082420
Numbers n such that P(n) < P(n+2) < P(n+1), where P(n) = largest prime factor of n (A006530).
2
4, 12, 16, 18, 36, 40, 42, 48, 50, 54, 60, 64, 66, 72, 75, 85, 96, 100, 108, 112, 117, 121, 128, 136, 150, 154, 156, 162, 180, 182, 184, 192, 196, 210, 217, 228, 240, 243, 245, 250, 256, 264, 266, 270, 276, 280, 282, 290, 294, 297, 301, 308, 312, 320, 325, 330, 333, 336
OFFSET
1,1
REFERENCES
Antal Balog, On the largest prime factor of consecutive integers, Abstracts Amer. Math. Soc., 25 (No. 2, 2002), p. 337, #975-11-76.
LINKS
P. Erdős and C. Pomerance, On the largest prime factors of n and n+1, Aequationes Math. 17 (1978), p. 311-321. [alternate link]
CROSSREFS
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Apr 25 2003
STATUS
approved