login
This site is supported by donations to The OEIS Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A082246 Primes that are the sum of 7 consecutive primes. 13
197, 223, 251, 281, 311, 401, 431, 463, 523, 593, 659, 719, 757, 827, 863, 947, 991, 1063, 1171, 1753, 1901, 2347, 2393, 2647, 2689, 2731, 2777, 2819, 2953, 3347, 3389, 3533, 3643, 3701, 3761, 3821, 4177, 4217, 4451, 4493, 5507, 5717, 5849, 5927, 6029 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Syed Iddi Hasan, Table of n, a(n) for n = 1..10000

EXAMPLE

2 + 3 + 5 + 7 + 11 + 13 + 17 = 58 = 2*29

3 + 5 + 7 + 11 + 13 + 17 + 19 = 75 = 3*5^2

5 + 7 + 11 + 13 + 17 + 19 + 23 = 95 = 5*19

7 + 11 + 13 + 17 + 19 + 23 + 29 = 119 = 7*17

11 + 13 + 17 + 19 + 23 + 29 + 31 = 143 = 11*13

13 + 17 + 19 + 23 + 29 + 31 + 37 = 169 = 13*13

17 + 19 + 23 + 29 + 31 + 37 + 41 = 197 (prime)

MATHEMATICA

Clear[Sum7Primes]; Sum7Primes[a_]:=Module[{p}, p=Prime[a]+Prime[a+1]+Prime[a+2] +Prime[a+3]+Prime[a+4]+Prime[a+5]+Prime[a+6]]; lst={}; Do[If[PrimeQ[p=Sum7Primes[n]], AppendTo[lst, p]], {n, 6!}]; lst (* Vladimir Joseph Stephan Orlovsky, Apr 06 2009 *)

Select[ListConvolve[{1, 1, 1, 1, 1, 1, 1}, Prime[Range[200]]], PrimeQ] (* Harvey P. Dale, Jul 12 2013 *)

Select[Total/@Partition[Prime[Range[200]], 7, 1], PrimeQ] (* Harvey P. Dale, Jul 24 2017 *)

PROG

(PARI) \\ primes in the sum of m odd number of consecutive primes. m=7

psumprm(m, n) = { sr=0; s=0; for(j=1, m, s+=prime(j); ); for(x=1, n, s = s - prime(x)+ prime(x+m); if(isprime(s), sr+=1.0/s; print1(s" ")); ); print(); print(sr) }

CROSSREFS

Cf. A180948.

Sequence in context: A162873 A182572 A152625 * A159809 A051371 A127339

Adjacent sequences:  A082243 A082244 A082245 * A082247 A082248 A082249

KEYWORD

easy,nonn

AUTHOR

Cino Hilliard, May 09 2003

EXTENSIONS

Corrected by Michael Somos, Feb 01 2004

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent | More pages
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy .

Last modified September 25 04:10 EDT 2017. Contains 292441 sequences.