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%I #15 Nov 21 2013 12:50:05
%S 1,1,4,2,4,7,6,8,34,12,12,14,13,16,11,19,23,20,24,52,23,40,48,39,58,
%T 35,40,41,54,40,60,69,46,41,49,136,172,100,118,91,128,117,71,78,217,
%U 126,95,121,99,71,107,120,79,71,144,75,104,78,129,100,74,169,174,116,352,203,238
%N Sequence from adding the twin primes and dividing by the digit sum of twin primes.
%C If necessary the result is rounded to the nearest integer.
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/TwinPrimes.html">Twin Primes</a>
%e (59 + 61) / (5+9+6+1) = 120/21 = 5.7 = 6 (rounded to the nearest integer)
%e 107 and 109 are twin primes.
%e Hence (107 + 109) / (1+0+7+1+0+9) = 216/18 = 12
%t Floor[1/2+Total[#]/Total[Flatten[IntegerDigits/@#]]]&/@ Select[Partition[Prime[Range[500]],2,1], Last[#]-First[#]==2&] (* _Harvey P. Dale_, Mar 23 2011 *)
%t f[n_] := Round[2 (n + 1)/(Plus @@ IntegerDigits[n] + Plus @@ IntegerDigits[n + 2])]; f@# & /@ Select[ Prime@ Range@ 1000, PrimeQ[# + 2] &] (* _Robert G. Wilson v_, Aug 16 2011 *)
%Y Cf. A001359.
%K base,nonn,less
%O 1,3
%A _Parthasarathy Nambi_, Aug 14 2010
%E More terms from Harvey P. Dale, Mar 23 2011.
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