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A162174
Primes classified by level.
17
5, 13, 19, 23, 31, 37, 43, 47, 53, 61, 73, 97, 113, 127, 131, 139, 151, 157, 163, 173, 181, 199, 211, 223, 233, 257, 263, 271, 293, 307, 313, 317, 337, 353, 373, 389, 397, 401, 421, 457, 479, 509, 523, 541, 547, 563, 571, 593, 607, 619, 647, 653, 661, 673, 691
OFFSET
1,1
COMMENTS
Conjecture : primes classified by level are rarefying among prime numbers.
A000040(n) = 2, 3, 7, A162175(n), a(n) [From Rémi Eismann, Jun 27 2009]
FORMULA
If for prime(n), A117078(n) (the weight) > A117563(n) (the level) then prime(n) is classified by level.
If for prime(n), A117078(n) (the weight) <= A117563(n) (the level) and A117078(n) <> 0 then prime(n) is classified by weight. [From Rémi Eismann, Jun 27 2009]
EXAMPLE
For prime(3)=5, A117078(3)=3 > A117563(3)=1 ; prime(3)=5 is classified by level. For prime(172)=1021, A117078(172)=337 > A117563(172)=3 ; prime(172)=1021 is classified by level.
CROSSREFS
Cf. A162175. [From Rémi Eismann, Jun 27 2009]
Sequence in context: A067463 A209663 A156111 * A171603 A118915 A084442
KEYWORD
nonn
AUTHOR
Rémi Eismann, Jun 27 2009
STATUS
approved