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A105575
Largest primes < numbers of the form 6k (duplicates removed).
2
5, 11, 17, 23, 29, 31, 41, 47, 53, 59, 61, 71, 73, 83, 89, 101, 107, 113, 131, 137, 139, 149, 151, 157, 167, 173, 179, 181, 191, 197, 199, 211, 227, 233, 239, 241, 251, 257, 263, 269, 271, 281, 283, 293, 311, 317, 331, 337, 347, 353, 359, 367, 373, 383, 389
OFFSET
1,1
EXAMPLE
11 is in the sequence because 11 is the largest prime < 12 = 6*2.
MATHEMATICA
PrevPrim[n_] := Block[{k = n - 1}, While[ !PrimeQ[k], k-- ]; k]; Union[ Table[ PrevPrim[6n], {n, 65}]] (* Robert G. Wilson v, May 21 2005 *)
NextPrime[#, -1]&/@(6*Range[100])//Union (* Harvey P. Dale, Sep 23 2017 *)
CROSSREFS
Cf. A105399.
Sequence in context: A038939 A314243 A357253 * A314244 A314245 A314246
KEYWORD
easy,nonn
AUTHOR
Giovanni Teofilatto, May 03 2005
EXTENSIONS
Corrected and extended by Robert G. Wilson v, May 21 2005
Edited, corrected and extended by Ray Chandler, Oct 17 2006
STATUS
approved