cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A127334 Numbers that are the sum of 7 consecutive primes.

Original entry on oeis.org

58, 75, 95, 119, 143, 169, 197, 223, 251, 281, 311, 341, 371, 401, 431, 463, 493, 523, 559, 593, 625, 659, 689, 719, 757, 791, 827, 863, 905, 947, 991, 1027, 1063, 1099, 1139, 1171, 1211, 1247, 1281, 1313, 1351, 1395, 1441, 1479, 1519, 1561, 1603, 1643
Offset: 1

Views

Author

Artur Jasinski, Jan 11 2007

Keywords

Comments

a(n) = absolute value of coefficient of x^6 of the polynomial Product_{j=0..6} (x - prime(n+j)) of degree 7; the roots of this polynomial are prime(n), ..., prime(n+6).

Crossrefs

Programs

  • GAP
    P:=Filtered([1..1000],IsPrime);; List([0..50],n->Sum([1+n..7+n],i->P[i])); # Muniru A Asiru, Apr 16 2018
  • Magma
    [&+[ NthPrime(n+k): k in [0..6] ]: n in [1..70] ]; // Vincenzo Librandi, Apr 03 2011
    
  • Maple
    seq(add(ithprime(i),i=n..6+n),n=1..50); # Muniru A Asiru, Apr 16 2018
  • Mathematica
    a = {}; Do[AppendTo[a, Sum[Prime[x + n], {n, 0, 6}]], {x, 1, 50}]; a
    Total/@Partition[Prime[Range[60]],7,1] (* Harvey P. Dale, May 14 2023 *)
  • PARI
    {m=48;k=7;for(n=0,m-1,print1(a=sum(j=1,k,prime(n+j)),","))} \\ Klaus Brockhaus, Jan 13 2007
    
  • PARI
    {m=48;k=7;for(n=1,m,print1(abs(polcoeff(prod(j=0,k-1,(x-prime(n+j))),k-1)),","))} \\ Klaus Brockhaus, Jan 13 2007
    
  • Python
    from sympy import prime
    def a(x): return sum(prime(x + n) for n in range(7))
    print([a(i) for i in range(1, 50)]) # Indranil Ghosh, Mar 18 2017
    
  • Sage
    BB = primes_first_n(62)
    L = []
    for i in range(55):
        L.append(sum(BB[i+j] for j in range(7)))
    L
    # Zerinvary Lajos, May 14 2007
    

Extensions

Edited by Klaus Brockhaus, Jan 13 2007