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

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, 18, 9, 9, 93, 27, 40, 12, 81, 6, 50, 53, 36, 58, 70, 9, 126, 12, 45, 18, 68, 83, 27, 12, 18, 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

Offset

1,2

Comments

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.

Links

Table of n, a(n) for n=1..75.

Example

2 '' 3 '4' 5 '6' 7 '8910' 11 '12' 13 '141516' 17 '18' 19 '202122' 23 '2425262728' 29,...

Mathematica

Table[Total[Flatten[IntegerDigits/@Range[Prime[n]+1, Prime[n+1]-1]]], {n, 200}] # Zak Seidov, Nov 13 2009

Crossrefs

Cf. A175038 [Zak Seidov, Nov 13 2009]

Sequence in context: A079803 A061361 A332986 * A309334 A263319 A062046

Adjacent sequences: A113607 A113608 A113609 * A113611 A113612 A113613

Keyword

base,easy,nonn

Author

Amarnath Murthy, Nov 09 2005

Extensions

More terms from Elizabeth A. Blickley (Elizabeth.Blickley(AT)gmail.com), Mar 10 2006

Status

approved