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A051268 Numbers n such that maximal value of prime divisors of reduced residue system for n is 4. 3
211, 221, 223, 227, 229, 233, 239, 241, 247, 251, 253, 257, 263, 269, 271, 277, 281, 283, 289, 293, 299, 307, 311, 313, 317, 319, 323, 331, 337, 341, 343, 347, 349, 353, 359, 361, 367, 371, 373, 377, 379, 383, 389, 391, 397, 401, 403, 407, 409, 413 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Largest value of A001221(k) = 4 for 1 <= k <= n such that gcd(k, n) = 1, i.e., k in row n of A038566. - Michael De Vlieger, Aug 10 2017

LINKS

Michael De Vlieger, Table of n, a(n) for n = 1..10000

MATHEMATICA

Block[{n = 4, P}, P = Product[Prime@ i, {i, n}]; P + Position[#, n][[All, 1]] &@ Array[Max@ Map[PrimeNu, Cases[Range@ #, k_ /; CoprimeQ[#, k]]] &, 175, P + 1]] (* Michael De Vlieger, Aug 10 2017 *)

CROSSREFS

Cf. A001221, A002110, A006862, A038566, A048597, A051250, A051265, A051266, A051267.

Sequence in context: A064826 A136601 A108406 * A159911 A133959 A133960

Adjacent sequences:  A051265 A051266 A051267 * A051269 A051270 A051271

KEYWORD

nonn,changed

AUTHOR

Labos Elemer

EXTENSIONS

More terms from Michael De Vlieger, Aug 10 2017

STATUS

approved

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Last modified August 19 14:06 EDT 2017. Contains 290808 sequences.