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%I #3 Mar 30 2012 18:52:35
%S 2,4,6,12,18,30,42,60,72,102,108,138,150,180,192,198,228,240,270,282,
%T 312,348,420,432,462,522,570,600,618,642,660,810,822,828,858,882,1020,
%U 1032,1050,1062,1092,1152,1230,1278,1290,1302,1320,1428,1452,1482,1488
%N Even single (or even isolated) numbers.
%C Two together with average of twin prime pairs.
%p Contribution from _R. J. Mathar_, Apr 14 2010: (Start)
%p isA007510 := proc(n) if isprime(n) then not isprime(n+2) and not isprime(n-2) ; else false; end if; end proc:
%p isA014574 := proc(n) if not isprime(n) then isprime(n+1) and isprime(n-1) ; else false; end if; end proc:
%p A167777 := proc(n) if n = 1 then 2; else for a from procname(n-1)+2 by 2 do if isA007510(a) or isA014574(a) then return(a) ; end if; end do ; end if; end proc:
%p seq(A167777(n),n=1..60) ; (End)
%Y Cf. A014574 (average of twin prime pairs), A167706 (the single or isolated numbers).
%K nonn
%O 1,1
%A _Juri-Stepan Gerasimov_, Nov 11 2009
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