A190501 Number of Ramanujan primes R_k such that 2^(n-1) < R_k <= 2^n.
0, 1, 0, 0, 1, 2, 3, 6, 10, 19, 33, 62, 118, 208, 409, 740, 1418, 2676, 5043, 9638, 18248, 34949, 66752, 127880, 245489, 472113, 908302, 1751624, 3381546, 6534616, 12645372, 24490255, 47485123, 92152929, 178987716, 347943866, 676925069, 1317911597, 2567659990, 5005877954, 9765539069, 19062301793, 37230980158, 72756216207, 142253989491, 278275735952, 544621563320, 1066382258001
Offset: 0
Keywords
Links
- Dana Jacobsen, Table of n, a(n) for n = 0..56
Programs
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PARI
\\ With RR[.] is a list of A104272(.). The output of this program is (for n>=1) n, A190502(n), and RR[a(n)], a(n). j=0;while(2^j
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Perl
use ntheory ":all"; say "$ ",ramanujan_prime_count(1 << $) - ramanujan_prime_count(1 << ($-1)) for 0..56; # _Dana Jacobsen, May 05 2017
Extensions
Extended by T. D. Noe, May 11 2011
Modified the name as to match offset to A190502 and added leading term, John W. Nicholson, May 12 2011
Extended to n = 32 by John W. Nicholson, Dec 01 2012
Extended to n = 47, using A190502 data, by John W. Nicholson, Jan 31 2016