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Primes in A001855.
1

%I #22 Sep 30 2024 15:47:56

%S 3,5,11,17,29,37,41,59,79,89,109,349,419,433,461,503,587,601,643,727,

%T 769,809,857,881,929,937,953,977,1009,1033,1049,1097,1129,1153,1193,

%U 1201,1217,1249,1289,1297,1321,1361,1409,1433,1481,1489,1553,1601,1609

%N Primes in A001855.

%H Paolo Xausa, <a href="/A123533/b123533.txt">Table of n, a(n) for n = 1..10000</a>

%H Wikipedia, <a href="http://en.wikipedia.org/wiki/Akra-Bazzi_method">Akra-Bazzi method</a>. As of 10 Nov 2006, this article correctly gives the asymptotic, but incorrectly refers to merge-sort rather than binary insertion sort.

%p A001855 := proc(n) local c ; c := ceil(log[2](n)) ; n*c-2^c+1 ; end: for n from 1 to 300 do srts := A001855(n) : if isprime(srts) then printf("%d, ",srts) ; fi ; od : # _R. J. Mathar_, Dec 16 2006

%t Select[Accumulate[BitLength[Range[0, 300]]], PrimeQ] (* _Paolo Xausa_, Jun 28 2024 *)

%Y Intersection of A000040 and A001855.

%Y Cf. A001768, A029837, A003071, A000337, A030190, A030308, A061168.

%K easy,nonn

%O 1,1

%A _Jonathan Vos Post_, Nov 10 2006

%E Corrected and extended by _R. J. Mathar_, Dec 16 2006