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.

A203619 Numbers that are a sum of m=3 successive primes and also a product of m=3 (other) successive primes.

Original entry on oeis.org

33263, 7566179, 10681031, 29884301, 51881689, 94593973, 182918137, 187466723, 319512181, 682238471, 799964687, 3926804047, 4047409651, 4881262679, 11857438631, 13418999327, 19184166361, 20428396159, 20743879777, 32573603551, 34148299187, 56372241473, 72215998451
Offset: 1

Views

Author

Zak Seidov, Feb 09 2012

Keywords

Comments

Indices of initial addends (summands) are 1343, 184557, 254101, 662222, 1108908, 1946623, 3616497, 3700883, 6114024, 12508273, 14539139, 65654476, 67568267, 80729196.
Initial addends (summands) are 11083, 2522057, 3560329, 9961421, 17293891, 31531301, 60972697, 62488883, 106504039, 227412803, 266654879, 1308934661, 1349136511, 1627087549.
Indices of initial factors are 10, 44, 47, 63, 73, 87, 103, 104, 123, 151, 157, 248, 250, 264.
Initial factors are 29, 193, 211, 307, 367, 449, 563, 569, 677, 877, 919, 1571, 1583, 1693.

Examples

			33263 = 11083+11087+11093 = 29*31*37,
7566179 = 2522057+2522059+2522063 = 193*197*199,
10681031 = 3560329+3560339+3560363 = 211*223*227,
4881262679 = 1627087549+1627087559+1627087571 = 1693*1697*1699.
		

Crossrefs

Intersection of A034961 and A046301.
Cf. A034961 (sums of three consecutive primes), A046301 (product of 3 successive primes).

Programs

  • PARI
    list(lim)={
        my(v=List(),p,q,p1,q1,r1,t);
        t=nextprime(lim^(1/3));
        while(t*precprime(t-1)*precprime(precprime(t-1)-1)t,r1=q1;q1=p1;p1=precprime(p1-1));
            if(p1+q1+r1==t,listput(v,t));
            p=q;q=r
        );
        Vec(v)
    }; \\ Charles R Greathouse IV, Feb 13 2012