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.

A125312 Moessner triangle based on primes.

Original entry on oeis.org

2, 3, 5, 10, 21, 13, 48, 105, 80, 29, 264, 628, 553, 232, 47, 1730, 4378, 4235, 2059, 543, 73, 13024, 34620, 36078, 19553, 6063, 1095, 107, 110542, 306362, 339554, 200769, 70350, 15166, 2000, 151, 1044900, 3003012, 3507070, 2228398, 861305, 212514
Offset: 1

Views

Author

Gary W. Adamson, Dec 10 2006

Keywords

Comments

Row sums are 2, 8, 44, 262, 1724, 13024, ... Conjecture: log row n-th sum tends to (2n-3) + some unknown fractional part. E.g., log 1724 = 7.45... while log 13024 = 9.43... Right border = A011756.

Examples

			First few rows of the triangle are:
     2;
     3,    5;
    10,   21,   13;
    48,  105,   80,   29;
   164,  628,  553,  232,  47;
  1736, 4378, 4235, 2059, 543, 73;
  ...
		

References

  • J. H. Conway and R. K. Guy, "The Book of Numbers", Springer-Verlag, 1996, p. 64.

Crossrefs

Formula

Begin with the primes and circle every (n*(n+1)/2)-th prime: 1, 5, 13, 29, 47, ... = A011756. Following the instructions in A125714, take partial sums of the uncircled terms, making this row 2. Circle the terms in row 2 one place to the left of row 1 terms. Take partial sums of the uncircled terms, continuing with analogous procedures for subsequent rows.

Extensions

Corrected and extended by Joshua Zucker, Jun 17 2007