|
|
A341700
|
|
Sum of the primes p satisfying n < p <= 2n.
|
|
2
|
|
|
2, 3, 5, 12, 7, 18, 24, 24, 41, 60, 49, 72, 59, 59, 88, 119, 102, 102, 120, 120, 161, 204, 181, 228, 228, 228, 281, 281, 252, 311, 341, 341, 341, 408, 408, 479, 515, 515, 515, 594, 553, 636, 593, 593, 682, 682, 635, 635, 732, 732, 833, 936, 883, 990, 1099, 1099
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
1,1
|
|
COMMENTS
|
For n >= 2, a(n) is the sum of the prime numbers appearing in the 2nd row of an n X n square array whose elements are the numbers from 1..n^2, listed in increasing order by rows. - Wesley Ivan Hurt, May 17 2021
|
|
LINKS
|
|
|
FORMULA
|
a(n) = A073837(n) if n is not a prime. Otherwise, a(n) = A073837(n)-n.
|
|
EXAMPLE
|
a(7) = 24 = 11+13 (sum of primes larger than 7 and less than or equal to 14).
|
|
MATHEMATICA
|
Array[Total@ Select[Range[# + 1, 2 #], PrimeQ] &, 56] (* Michael De Vlieger, Feb 17 2021 *)
|
|
PROG
|
(Python)
from sympy import nextprime
s, m = 0, nextprime(n)
while m <= 2*n:
s += m
m = nextprime(m)
return s
|
|
CROSSREFS
|
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|