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A182869 Joint-rank array of prime powers: p(i)^j, i>=1, j>=1, read by antidiagonals. 7

%I #11 Mar 30 2012 18:57:12

%S 1,3,2,6,7,4,10,15,14,5,18,32,42,23,8,27,68,136,86,41,9,44,152,482,

%T 392,244,53,11,70,359,1880,2001,1773,360,91,12,117,893,7771,11211

%N Joint-rank array of prime powers: p(i)^j, i>=1, j>=1, read by antidiagonals.

%C Joint-rank arrays are defined in the first comment at A182801. A182869 is a permutation of the positive integers.

%F T(i,j)=Sum{floor(j*log(p(i))/log(p(h)): h>=1},

%F where p(i) denotes the i-th prime.

%e First, arrange the prime powers in rows:

%e 2....4....8....16....32...

%e 3....9...27....81...243...

%e 5...25..125...625..3125...

%e Then replace each prime power by its rank when they are all jointly ranked:

%e 1....3....6....10.....18...

%e 2....7...15....32.....68...

%e 4...14...42...136....482...

%e 5...23...86...392...2001...

%e 8...41..244..1773..14901...

%t T[i_,j_]:=Sum[Floor[j*Log[Prime[i]]/Log[Prime[h]]],{h,1,PrimePi[Prime[i]^j]}];

%t TableForm[Table[T[i,j],{i,1,6},{j,1,6}]]

%Y Cf. A000961, A027883, A182801, A182870, A182908.

%K nonn,tabl

%O 1,2

%A _Clark Kimberling_, Dec 09 2010

%E Corrected and extended by _Clark Kimberling_, Dec 13 2010

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