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A060333
Primes which are the sum of eight consecutive composite numbers.
3
193, 277, 353, 433, 443, 613, 643, 653, 673, 683, 739, 881, 1109, 1129, 1237, 1511, 1531, 1609, 1619, 1697, 1873, 1999, 2017, 2027, 2113, 2207, 2239, 2281, 2371, 2447, 2621, 2657, 2677, 2687, 2749, 2801, 2833, 2843, 2909, 2927, 3023, 3083, 3121, 3167
OFFSET
1,1
LINKS
MAPLE
comps:= remove(isprime, [$4..1000]):
S:= add(comps[i+1..i-8], i=0..7):
select(isprime, S); # Robert Israel, Dec 12 2019
MATHEMATICA
composite[ n_Integer ] := (k = n + PrimePi[ n ] + 1; While[ k - PrimePi[ k ] - 1 != n, k++ ]; k); a = {}; Do[ p = Sum[ composite[ n + k ], {k, 0, 7} ]; If[ PrimeQ[ p ], a = Append[ a, p ] ], {n, 1, 600} ]; a
Select[Total /@ Partition[ Select[ Range@ 500, CompositeQ], 8, 1], PrimeQ] (* Giovanni Resta, Dec 13 2019 *)
KEYWORD
nonn
AUTHOR
Robert G. Wilson v, Mar 30 2001
STATUS
approved