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A080370 Number of distinct values among the differences prime(j)-prime(i), 1 <= i < j <= n. 5

%I

%S 0,1,3,5,8,10,13,15,18,22,24,28,31,33,36,40,44,46,50,53,55,59,62,66,

%T 70,74,76,79,81,84,90,95,99,101,106,109,113,117,120,124,128,130,135,

%U 138,141,143,149,155,159,161,165,169,171,176,180,184,188,191,195,198,200

%N Number of distinct values among the differences prime(j)-prime(i), 1 <= i < j <= n.

%e n=1: no differences arise; n=3: primes={2, 3, 5}, C[3, 2]=3, differences={3, 2, 1}, a(3)=3;

%e n=7: primes={2, 3, 5, 7, 11, 13, 17}, differences={15, 14, 12, 10, 6, 4, 11, 10, 8, 6, 2, 9, 8, 6, 4, 5, 4, 2, 3, 2, 1}, distinct terms ={15, 14, 12, 11, 10, 9, 8, 6, 5, 4, 3, 2, 1}, a(7)=13.

%t f[n_] := Length[ Union[ Flatten[ Table[ Prime[i] - Prime[j], {i, 2, n}, {j, i - 1}]] ]]; Table[ f[n], {n, 61}] (* _Robert G. Wilson v_, Jul 30 2004 *)

%K nonn

%O 1,3

%A _Labos Elemer_, Feb 26 2003

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Last modified July 1 02:58 EDT 2022. Contains 354947 sequences. (Running on oeis4.)