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%I #18 Oct 18 2023 11:50:33
%S 0,10,73,574,4543,37723,320991,2796946,24758534,222126290,2014200162
%N Number of strong primes < 10^n.
%C The number of strong primes < n ~ sum of strong primes < sqrt(n). The number of strong primes < 10^11 = 2014200162 and the sum of strong primes < 10^5.5 = 1972716560, for an error of 0.0206.
%H Cino Hilliard, <a href="http://groups.google.com/group/sumprimes/web/count-and-sum-strong-primes?msg=sap">Sum of Strong Primes</a>. [broken link]
%F Given 3 consecutive primes p1,p2,p3, p2 is a strong prime if p2 > (p1+p2)/2.
%F Or, primes that are greater than the arithmetic mean of their immediate surrounding primes.
%e The strong primes < 10^2 are 11, 17, 29, 37, 41, 59, 67, 71, 79, 97. These add up to 10 which is the second term in the sequence.
%o (Other) See the link for Gcc programs that count and sum these primes.
%K nonn,more
%O 1,2
%A _Cino Hilliard_, Apr 19 2009
%E Edited by _N. J. A. Sloane_, Apr 20 2009
%E a(11) corrected by _Bill McEachen_, Oct 18 2023
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