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A164554 Ramanujan primes A104272(n) for which A104272(n) = A080359(n). +0
9
2, 71, 101, 181, 239, 241, 269, 349, 373, 409, 419, 433, 439, 491, 593, 599, 601, 607, 647, 653, 659, 823, 827, 857, 947, 1021, 1031, 1061, 1063, 1091, 1103, 1301, 1427, 1429, 1447, 1451, 1489, 1553, 1559, 1567, 1601, 1607, 1609, 1789, 1867, 1871, 1913, 1999, 2003 (list; graph; listen)
OFFSET

1,1

COMMENT

For every n>=1, A104272(n) >= A080359(n), and the sequence shows where the inequality becomes an equality.

Let prime(m) < a(n)/2 < prime(m+1); then primes p<q exist such that p is in the interval (2*Prime(m), a(n))

and such that q is in the interval (a(n), 2*Prime(m+1)).

LINKS

V. Shevelev, On critical small intervals containing primes, arXiv:0908.2319 [math.NT] [From Vladimir Shevelev (shevelev(AT)bgu.ac.il), Aug 20 2009]

EXAMPLE

a(2)=71, such that 31<71/2<37, and we see that p=67 is in interval (62, 71) and q=73 is in interval (71, 74).

CROSSREFS

A104272 A080359 A164368 A164333 A164288 A164294

KEYWORD

nonn,new

AUTHOR

Vladimir Shevelev (shevelev(AT)bgu.ac.il), Aug 15 2009

EXTENSIONS

Terms beyond 659 from R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Dec 17 2009

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Last modified December 17 23:40 EST 2009. Contains 171025 sequences.


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