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Ramanujan primes A104272 that are primes p(k) such that (k+1)*p(k)>k*p(k+1).
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%I #11 Dec 21 2013 03:59:32

%S 2,11,17,29,41,59,71,101,107,127,149,179,227,229,281,307,311,347,349,

%T 419,431,439,461,487,569,599,641,643,659,739,769,809,821,823,853,857,

%U 937,967,983,1009,1019,1031,1049,1061,1087,1091,1151,1187,1217,1229

%N Ramanujan primes A104272 that are primes p(k) such that (k+1)*p(k)>k*p(k+1).

%C Non-Ramanujan primes (A174635) that are primes p(k) such that (k+1)*p(k)>k*p(k+1): 137, 163, 191, 197, 223, 277, 379, 397, 457, 499, 521, 613, 617, 673, 757, 859, 877, 907, 1093, 1181, 1213, 1223, 1231,...

%C Primes p(k) such that (k+1)*p(k)> k*p(k+1): 2, 11, 17, 29, 41, 59, 71,...

%C primes p(k) such that (k+1)*p(k) - k*p(k+1)=1: 2, 11,...

%C Primes p(m) such that (m+1)*p(m) < m*p(m+1): 3, 5, 7, 13, 19, 23, 31,...

%e Ramanujan prime 2 is in this sequence because 2 = p(1) such that (1 + 1)*p(1) = 2*2 = 4 > 1*p(1 + 1) = 3;

%e Ramanujan prime 11 is in this sequence because 11 = p(5) such that (5 + 1)*p(5) = 6*11 = 66 > 5*p(5 + 1) = 65.

%K nonn,less

%O 1,1

%A _Irina Gerasimova_, Dec 17 2013