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Prime means of 12 horizontal, vertical and main diagonal sums associated with primes in A094458.
1

%I #5 Mar 31 2012 10:32:40

%S 223,641,2531,3271,4153,6691,11497,13109,13499,21379,21467,24379,

%T 29243,30169,31379,33349,34127,36653,41047,43049,43759,45971,50909,

%U 50951,51241,54181,54437,62303,62981,65557,81677,87277,93131,97583,101977

%N Prime means of 12 horizontal, vertical and main diagonal sums associated with primes in A094458.

%F Arrange 25 consecutive primes in a 5 X 5 grid wherein YJKLM, XIBCN, WHADO, VGFEP, UTSRQ are the first through 5th horizontal rows of primes. Then sum the rows horizontally, vertically and along the two main diagonals. Total the 12 sums, divide by 12 and if the mean is integral and prime, adjoin to the sequence.

%e a(1)=223 because 223 is the integral and prime mean of the 12 sums of 25 consecutive primes arranged in a 5 X 5 grid wherein the first prime is 3.

%Y Cf. A094458 A094455.

%K easy,nonn

%O 1,1

%A _Enoch Haga_, May 06 2004