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A113610 Sum of digits of all composite numbers between prime(n) and prime(n+1). 1

%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

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Last modified February 25 00:18 EST 2024. Contains 370308 sequences. (Running on oeis4.)