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A176834
List of all primes p such that 3*A099609(2n-1)<p<3*A099609(2n).
0
7, 11, 13, 17, 19, 37, 53, 89, 127, 179, 181, 307, 449, 541, 577, 593, 683, 719, 809, 811, 937, 1259, 1297, 1567, 1709, 1801, 1979, 2467, 2647, 3061, 3187, 3457, 3691, 3833, 3907, 4283, 4357, 4447, 4463, 4861, 5003, 5167, 5849, 5851, 6247, 6263, 6337, 6389
OFFSET
1,1
COMMENTS
Where A099609 is a naive list of twin primes (A077800 prefixed by 2,3).
EXAMPLE
a(1)=7 because 3*A099609(2*1-1)=6<7(prime)<3*A099609(2*1)=9; a(2)=11 and a(3)=13 because 3*A099609(2*2-1)=9<11(prime)<13(prime)<3*A099609(2*2)=15; a(4)=17 and a(5)=19 because 3*A099609(2*3-1)=15<17(prime)<19(prime)<3*A099609(2*3)=21.
MAPLE
Contribution from R. J. Mathar, May 10 2010: (Start)
A077800 := proc(n) if type(n, 'even') then A006512(n/2) ; else A001359((n+1)/2) ; end if; end proc:
A099609 := proc(n) if n <= 2 then n+1 ; else A077800(n-2) ; end if; end proc:
for n from 1 to 100 do lpr := 3*A099609(2*n-1) ; upr := 3*A099609(2*n) ; for p from lpr+1 to upr-1 do if isprime(p) then printf("%d, ", p) ; end if; end do: end do: (End)
CROSSREFS
Cf. A171821.
Sequence in context: A243768 A141636 A214786 * A098414 A293201 A110583
KEYWORD
nonn
AUTHOR
EXTENSIONS
Corrected (3691 inserted) by R. J. Mathar, May 10 2010
STATUS
approved