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A328226
Primitive elements of A278638.
1
6, 15, 20, 21, 28, 33, 35, 44, 52, 55, 65, 68, 76, 77, 85, 91, 95, 115, 117, 119, 133, 143, 145, 153, 155, 161, 171, 184, 185, 187, 203, 205, 207, 209, 215, 217, 221, 232, 235, 247, 248, 253, 259, 261, 265, 279, 287, 296, 299, 301, 305, 319, 323, 328, 329, 333, 335, 341
OFFSET
1,1
COMMENTS
A number k belongs to this sequence if k is a term of A278638, while its proper divisors are not. It follows that A278638 is formed by the multiples of the terms of this sequence.
CROSSREFS
KEYWORD
nonn
AUTHOR
Max Alekseyev, Oct 08 2019
STATUS
approved