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A210957
Prime pair (p, q), p<=q, such that p + q = 2*n and p*q is the minimal product.
1
2, 2, 3, 3, 3, 5, 3, 7, 5, 7, 3, 11, 3, 13, 5, 13, 3, 17, 3, 19, 5, 19, 3, 23, 5, 23, 7, 23, 3, 29, 3, 31, 5, 31, 7, 31, 3, 37, 5, 37, 3, 41, 3, 43, 5, 43, 3, 47, 5, 47, 7, 47, 3, 53, 5, 53, 7, 53, 3, 59, 3, 61, 5, 61, 7, 61, 3, 67, 5, 67, 3, 71, 3, 73
OFFSET
2,1
COMMENTS
A020481 and A020482 interleaved.
FORMULA
p_n = A020481(n), n >= 2.
q_n = A020482(n), n >= 2.
p_n + q_n = 2*n, n >= 2.
p_n * q_n = A073046(n), n >= 2.
EXAMPLE
-----------------------------------
2*n A073046(n)
Pair = =
n (p, q) p+q p*q
-----------------------------------
2 (2, 2) 4 4
3 (3, 3) 6 9
4 (3, 5) 8 15
5 (3, 7) 10 21
6 (5, 7) 12 35
7 (3, 11) 14 33
8 (3, 13) 16 39
9 (5, 13) 18 65
10 (3, 17) 20 51
11 (3, 19) 22 57
12 (5, 19) 24 95
CROSSREFS
KEYWORD
nonn
AUTHOR
Omar E. Pol, Jun 29 2012
STATUS
approved