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%I #10 Apr 29 2023 12:06:26
%S 1,2,4,6,9,12,15,24,21,33,65,36,30,42,45,148,63,72,60,84,81,75,90,129,
%T 114,132,144,126,159,120,105,156,150,168,198,189,219,222,430,180,318,
%U 165,252,291,195,240,321,231,225,294,610,210,372,417,270,414,790,357
%N Index of first occurrence of n in A069360.
%C a(n) = smallest k > 0 such that there are n prime pairs (p,q), p < q, with (p+q)/2 = 2*k.
%H Klaus Brockhaus, <a href="/A135146/b135146.txt">Table of n, a(n) for n = 0..1000</a>
%e Number of prime pairs (p,q) with (p+q)/2 = 2*1 is 0, hence a(0) = 1.
%e 9 is the smallest k such that there are four prime pairs (p,q) with (p+q)/2 = 2*k: (5+31)/2 = (7+29)/2 = (13+23)/2 = (17+19)/2 = 18 = 2*9. Hence a(4) = 9.
%Y Cf. A069360, A134677 (records in A069360), A134678 (where records occur in A069360).
%K nonn
%O 0,2
%A _Klaus Brockhaus_, Nov 20 2007