

A071059


Number of ways of pairing even numbers in the range 1 to n with odd numbers in the range n+1 to 2n such that each pair sums to a prime.


2



1, 1, 1, 1, 1, 2, 2, 6, 4, 7, 6, 11, 11, 53, 53, 181, 171, 939, 925, 4432, 4545, 15811, 15583, 67891, 68193, 434963, 388975, 2718150, 3113343, 21580655, 18425145, 92370364, 94887088, 564878656, 572364768, 4545704064, 4092294083
(list;
graph;
refs;
listen;
history;
text;
internal format)



OFFSET

1,6


LINKS

Table of n, a(n) for n=1..37.


FORMULA

a(2n) = A071058(2n).


EXAMPLE

a(6)=2 because there are two ways: 2+9, 4+7, 6+11 and 2+11, 4+9, 6+7.


CROSSREFS

The product of this sequence and A071058 gives A070897.
Sequence in context: A067804 A074911 A174222 * A256468 A061108 A284918
Adjacent sequences: A071056 A071057 A071058 * A071060 A071061 A071062


KEYWORD

nice,nonn


AUTHOR

T. D. Noe, May 25 2002


EXTENSIONS

More terms from David W. Wilson, May 27 2002
a(31)a(37) from Donovan Johnson, Aug 12 2010


STATUS

approved



