Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).
%I #5 Dec 05 2013 19:57:07
%S 0,4,6,18,3,18,9,9,40,3,35,27,6,27,43,55,6,50,36,9,65,27,70,84,36,3,
%T 18,9,9,93,27,40,12,81,6,50,53,36,58,70,9,126,12,45,18,68,83,27,12,18,
%U 55,6,99,55,58,70,9,65,45,12,135,147,27,6,27,126,50,99,15,27,70,84,68,80,36
%N Sum of digits of all composite numbers between prime(n) and prime(n+1).
%C Conjecture: For n > 9 if a(n) > a(n+1) < a(n+2) then prime(n) and prime(n+1) form a twin prime pair.
%e 2 '' 3 '4' 5 '6' 7 '8910' 11 '12' 13 '141516' 17 '18' 19 '202122' 23 '2425262728' 29,...
%t Table[Total[Flatten[IntegerDigits/@Range[Prime[n]+1,Prime[n+1]-1]]],{n, 200}] # _Zak Seidov_, Nov 13 2009
%Y Cf. A175038 [_Zak Seidov_, Nov 13 2009]
%K base,easy,nonn
%O 1,2
%A _Amarnath Murthy_, Nov 09 2005
%E More terms from Elizabeth A. Blickley (Elizabeth.Blickley(AT)gmail.com), Mar 10 2006