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A090325
Least (distinct) k such that k, k+n, k+2n are all composite. Rearrangement of composite numbers.
1
8, 4, 6, 10, 15, 9, 14, 12, 16, 18, 22, 20, 25, 21, 24, 26, 28, 27, 30, 32, 33, 34, 35, 36, 38, 39, 42, 40, 46, 44, 49, 48, 45, 50, 51, 52, 54, 56, 55, 58, 63, 57, 62, 60, 65, 64, 68, 66, 70, 69, 72, 74, 76, 75, 77, 78, 81, 80, 82, 84, 85, 86, 87, 88, 90, 92, 91, 94, 93, 95, 98
OFFSET
1,1
LINKS
MAPLE
N:= 100: # to get all terms before the first term > N
Avail:= remove(isprime, [$4..N]):
for n from 1 while Avail <> [] do
for a in Avail while isprime(a+n) or isprime(a+2*n) do od:
if a = Avail[-1] and isprime(a+n) or isprime(a+2*n) then break fi;
A[n]:= a;
Avail:= subs(a=NULL, Avail);
od:
seq(A[i], i=1..n-1); # Robert Israel, Nov 19 2017
CROSSREFS
Sequence in context: A266556 A199434 A253073 * A090469 A322743 A168546
KEYWORD
nonn
AUTHOR
Amarnath Murthy, Dec 02 2003
EXTENSIONS
More terms from David Wasserman, Nov 04 2005
STATUS
approved