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A190501
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Number of Ramanujan primes R_k such that 2^(n-1) < R_k <= 2^n.
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3
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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
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OFFSET
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0,6
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LINKS
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PROG
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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<RR[10^8], {n=1; while(RR[n]<=2^j, n++); pn=n-1; if(n<=1, print(j, " ", 0, " none"), print(j, " ", pn, " ", RR[pn], " ", pn-pn2)); pn2=pn; j++});
(Perl) use ntheory ":all"; say "$_ ", ramanujan_prime_count(1 << $_) - ramanujan_prime_count(1 << ($_-1)) for 0..56; # Dana Jacobsen, May 05 2017
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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