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A248005 Number of primes obtained in the first step of the long division of prime(n) by prime(i), i=2,...,n-1 (see example). 1

%I #10 Oct 19 2014 15:55:03

%S 1,1,1,2,3,2,3,3,3,5,4,4,5,4,5,4,4,5,7,7,4,7,7,5,6,6,7,9,7,8,9,7,8,8,

%T 9,10,5,7,8,11,9,13,10,10,7,9,8,12,11,12,10,12,12,12,10,10,14,12,11,

%U 12,13,10,12,10,13,15,13,11,12,12,15,17,12,13,13,16

%N Number of primes obtained in the first step of the long division of prime(n) by prime(i), i=2,...,n-1 (see example).

%H Peter J. C. Moses, <a href="/A248005/b248005.txt">Table of n, a(n) for n = 3..1002</a>

%e Let n=16, prime(16)=53. Consider the first step of the long division of 53 by 3:

%e 53

%e -3

%e 23

%e Since 23 is prime, then 3 contributes 1 into a(16); also in the first step of the long division of 53 by 5,17,23 (and only by them) we obtain primes (3,2,7). So a(16)=4.

%K nonn

%O 3,4

%A _Vladimir Shevelev_, Sep 29 2014

%E More terms from _Peter J. C. Moses_, Oct 12 2014

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Last modified September 13 15:18 EDT 2024. Contains 375908 sequences. (Running on oeis4.)