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A174521
Primes that are the sum of all composite numbers in-between prime numbers p(n) and p(n+2).
1
193, 673, 1873, 2207, 2833, 4391, 3023, 8209, 5903, 8999, 6047, 9643, 7537, 19843, 10273, 29399, 11953, 12433, 20879, 35999, 36241, 23761, 23831, 24907, 20353, 32401, 33403, 22367, 34129, 57367, 49123, 74311, 51197, 40037, 42773, 71399
OFFSET
1,1
COMMENTS
20+21+22+24+25+26+27+28=193,..
LINKS
MATHEMATICA
f[n_, x_]:=n*x+x*(x+1)/2; Select[Table[f[Prime[n], Prime[n+2]-Prime[n]-1]-Prime[n+1], {n, 6!}], PrimeQ[ # ]&]
Select[Table[Total[Select[Range[Prime[n], Prime[n+2]], CompositeQ]], {n, 1000}], PrimeQ] (* Harvey P. Dale, May 13 2017 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
STATUS
approved