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A060232
Smaller of twin primes whose mean (average) is a multiple of A002110(6)=30030.
3
180179, 270269, 300299, 330329, 390389, 420419, 540539, 660659, 840839, 1231229, 1261259, 1501499, 1621619, 1861859, 1921919, 1951949, 2012009, 2372369, 2762759, 2972969, 3663659, 3693689, 3723719, 3903899, 4084079
OFFSET
1,1
LINKS
Robert Israel, Table of n, a(n) for n = 1..10000 (first 642 terms from Muniru A Asiru)
EXAMPLE
For the pair {5735729,5735731} (5735729+5735731)/2 = 191*30030.
MAPLE
for n from 1 to 10^5 do if (ithprime(n+1) - ithprime(n)) = 2 and (ithprime(n+1) + ithprime(n)) mod 30030 = 0 then print(ithprime(n)); fi; od; # Muniru A Asiru, Jan 29 2018
# More efficient:
select(t -> isprime(t) and isprime(t+2), [seq(30030*k-1, k=1..10^3)]); # Robert Israel, Jan 29 2018
MATHEMATICA
Select[Partition[Prime[Range[300000]], 2, 1], #[[2]]-#[[1]]==2&&Divisible[Mean[ #], 30030]&][[All, 1]] (* Harvey P. Dale, Apr 23 2022 *)
PROG
(GAP) P:=Filtered([1..10^5], IsPrime);;
P1:=List(Filtered(Filtered(List([1..Length(P)-1], n -> [P[n], P[n+1]]), i -> i[2]-i[1]=2), j -> (j[1] + j[2]) mod 30030 = 0), k -> k[1]); # Muniru A Asiru, Jan 29 2018
CROSSREFS
KEYWORD
nonn
AUTHOR
Labos Elemer, Mar 21 2001
EXTENSIONS
Minor edits by Ray Chandler, Apr 04 2009
Definition clarified by Harvey P. Dale, Apr 23 2022
STATUS
approved