The On-Line Encyclopedia of Integer Sequences (OEIS)

Revision History for A371201 (Bold, blue-underlined text is an addition; faded, red-underlined text is a ~~deletion~~.)
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A371201

a(n) = Sum_{k=prime(n)..prime(n+1)-1} k, with a(0) = 1.
(history; published version)

#43 by OEIS Server at Sat Jun 01 20:07:05 EDT 2024

LINKS

Alois P. Heinz, <a href="/A371201/b371201_1.txt">Table of n, a(n) for n = 0..10000</a>

#42 by Alois P. Heinz at Sat Jun 01 20:07:05 EDT 2024

STATUS

editing

approved

Discussion

Sat Jun 01

20:07

OEIS Server: Installed first b-file as b371201.txt.

#41 by Alois P. Heinz at Sat Jun 01 20:07:01 EDT 2024

LINKS

Alois P. Heinz, <a href="/A371201/b371201_1.txt">Table of n, a(n) for n = 0..10000</a>

STATUS

approved

editing

#40 by Alois P. Heinz at Sat Jun 01 20:06:36 EDT 2024

STATUS

proposed

approved

#39 by Chai Wah Wu at Sat Jun 01 19:35:42 EDT 2024

STATUS

editing

proposed

#38 by Chai Wah Wu at Sat Jun 01 19:35:22 EDT 2024

FORMULA

a(n) = (prime(n+1)-prime(n))*(prime(n+1)+prime(n)-1)/2 for n>=1. - Chai Wah Wu, Jun 01 2024

PROG

return (q-p)*(p+q-1)>>1 # Chai Wah Wu, Jun 01 2024

#37 by Chai Wah Wu at Sat Jun 01 19:33:25 EDT 2024

PROG

(Python)

from sympy import nextprime, prime

def A371201(n):

if n == 0: return 1

q = nextprime(p:=prime(n))

return (q-p)*(p+q-1)>>1 # Chai Wah Wu, Jun 01 2024

STATUS

approved

editing

#36 by Joerg Arndt at Sat Apr 20 11:59:08 EDT 2024

STATUS

reviewed

approved

#35 by Michel Marcus at Sat Apr 20 11:46:15 EDT 2024

STATUS

proposed

reviewed

#34 by James C. McMahon at Sat Apr 20 11:30:53 EDT 2024

STATUS

editing

proposed