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%I #10 Mar 31 2015 00:28:35
%S 1,10,13,14,17,20,25,26,38,39,41,42,43,44,45,48,49,50,55,58,59,61,63,
%T 65,69,73,74,77,81,86,88,90,92,96,98,101,103,106,107,108,109,110,116,
%U 117,120,121,122,124,125,128,141,142,143,145,146,148,149,151,152,155,158,159,166,169
%N Numbers n for which the number of primes in the range [prime(n)*prime(n+1), prime(n+1)^2] is less than or equal to the number of primes in the range [prime(n)^2, prime(n)*prime(n+1)].
%C Positions where A256470 is zero or negative.
%H Antti Karttunen, <a href="/A256477/b256477.txt">Table of n, a(n) for n = 1..3128</a>
%t Select[Range@ 170, Count[Range[Prime[#] Prime[# + 1], Prime[# + 1]^2], _?PrimeQ] <= Count[Range[Prime[#]^2, Prime[#] Prime[# + 1]], _?PrimeQ] &] (* _Michael De Vlieger_, Mar 30 2015 *)
%o (Scheme, with _Antti Karttunen_'s IntSeq-library)
%o (define A256477 (MATCHING-POS 1 1 (lambda (n) (>= 0 (A256470 n)))))
%Y Complement: A256476.
%Y Union of A256471 and A256475.
%Y Cf. A256470.
%K nonn
%O 1,2
%A _Antti Karttunen_, Mar 30 2015