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A285690
a(1) = 2; a(n + 1) = smallest prime > a(n) such that a(n + 1) - a(n) is the product of five primes.
5
2, 569, 601, 673, 853, 1021, 1069, 1117, 1229, 1277, 1439, 1471, 1543, 1663, 1783, 1831, 1879, 1951, 1999, 2111, 2143, 2251, 2371, 2539, 2647, 2719, 2767, 2879, 2927, 2999, 3079, 3187, 3259, 3307, 3469, 3517, 3637, 3709, 3821, 3853, 4021, 4093, 4201
OFFSET
1,1
COMMENTS
First differences: 567, 32, 72, 180, 168, 48, 48, 112, 48, 162, 32, 72, 120, 120, 48, 48, 72, 48, 112, 32, ...
LINKS
MAPLE
A[1]:= 2:
for n from 2 to 100 do
p:= A[n-1];
do
p:= nextprime(p);
if numtheory:-bigomega(p-A[n-1])=5 then A[n]:= p; break fi
od od:
seq(A[i], i=1..100); # Robert Israel, Nov 04 2019
MATHEMATICA
NestList[Module[{p = NextPrime@ #}, While[PrimeOmega[p - #] != 5, p = NextPrime@ p]; p] &, 2, 40] (* Michael De Vlieger, Apr 25 2017 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Zak Seidov, Apr 24 2017
STATUS
approved