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.

A307357 Row sums of triangle A307116.

Original entry on oeis.org

1, 2, 4, 8, 5, 10, 11, 10, 17, 22, 12, 24, 25, 18, 30, 36, 20, 40, 47, 24, 42, 42, 32, 46, 58, 34, 50, 58, 52, 60, 63, 50, 73, 64, 56, 84, 82, 56, 83, 88, 58, 86, 88, 74, 99, 96, 76, 106, 96, 90, 136, 124, 75, 108, 131, 82, 106, 142, 130, 132, 127, 104, 129
Offset: 0

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Author

Rémy Sigrist, Apr 04 2019

Keywords

Comments

The scatterplot of the sequence shows 3 beams of points; this could be related to the regular structure visible on both sides of the triangle A307116.

Examples

			The first terms, alongside the corresponding rows in A307116, are:
  n  a(n)  Row n of A307116
  -  ----  ----------------
  0     1           1
  1     2          1 1
  2     4         1 2 1
  3     8        1 3 3 1
  4     5       1 1 1 1 1
  5    10      1 2 2 2 2 1
  6    11     1 3 1 1 1 3 1
  7    10    1 1 1 2 2 1 1 1
  8    17   1 2 2 3 1 3 2 2 1
  9    22  1 3 1 5 1 1 5 1 3 1
		

Crossrefs

Cf. A307116.

Programs

  • PARI
    fibs = Set(vector(100,k,fibonacci(k)))
    f(s) = if (setsearch(fibs, s), s, 1)
    { for (r=0, 62, row = vector(r+1, k, if (k==1||k==r+1, 1, f(row[k-1]+row[k]))); print1 (vecsum(row) ", ")) }

Formula

a(n) = Sum_{k = 0..n} A307116(n, k).