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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 (list; graph; refs; listen; history; text; internal format)
OFFSET

2,1

COMMENTS

A020481 and A020482 interleaved.

LINKS

Table of n, a(n) for n=2..75.

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

Cf. A000040, A002373, A073046, A210967.

Sequence in context: A136132 A136545 A125843 * A306246 A147665 A222820

Adjacent sequences:  A210954 A210955 A210956 * A210958 A210959 A210960

KEYWORD

nonn

AUTHOR

Omar E. Pol, Jun 29 2012

STATUS

approved

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Last modified February 23 15:34 EST 2020. Contains 332167 sequences. (Running on oeis4.)