

A308052


a(n) = nextprime(ceiling(n/2)1), where nextprime(n) is the smallest prime > n.


0



2, 2, 2, 2, 3, 3, 5, 5, 5, 5, 7, 7, 7, 7, 11, 11, 11, 11, 11, 11, 11, 11, 13, 13, 13, 13, 17, 17, 17, 17, 17, 17, 17, 17, 19, 19, 19, 19, 23, 23, 23, 23, 23, 23, 23, 23, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 31, 31, 31, 31, 37, 37, 37, 37, 37, 37
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OFFSET

1,1


COMMENTS

For n >= 3, a(n) is the smallest prime appearing among the larger parts of the partitions of n into two parts.


LINKS

Table of n, a(n) for n=1..68.
Index entries for sequences related to partitions


FORMULA

a(n) = A151800(ceiling(n/2)1).


EXAMPLE

a(7) = 5; 7 has three partitions into two parts: (6,1), (5,2) and (4,3). The smallest prime among the larger parts is 5, so a(7) = 5.


MATHEMATICA

Table[NextPrime[Ceiling[n/2]  1, 1], {n, 100}]


CROSSREFS

Cf. A151800.
Sequence in context: A081651 A269333 A029193 * A005858 A285798 A321346
Adjacent sequences: A308049 A308050 A308051 * A308053 A308054 A308055


KEYWORD

nonn,easy


AUTHOR

Wesley Ivan Hurt, May 10 2019


STATUS

approved



