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.

Showing 1-8 of 8 results.

A225263 a(k) such that A225258 column k of T(n,k) = n*k^3 - a(k) for large n.

Original entry on oeis.org

-1, 4, 18, 51, 91, 170, 249, 380, 520, 702, 882, 1171, 1378, 1710, 2057, 2447, 2795, 3297, 3690, 4306, 4808, 5449, 6049, 6906, 7479, 8268, 9115, 9993, 10812, 12000, 12792, 13936, 14925, 16106, 17308, 18753, 19745, 21203, 22615, 24258, 25475, 27235
Offset: 1

Views

Author

R. H. Hardin May 04 2013

Keywords

A225259 Number of distinct values of the sum of 2 products of three 0..n integers.

Original entry on oeis.org

3, 12, 36, 75, 157, 254, 434, 635, 911, 1237, 1734, 2162, 2908, 3611, 4461, 5435, 6734, 7879, 9568, 10964, 12861, 14913, 17438, 19426, 22381, 25251, 28482, 31624, 35879, 39100, 44165, 48267, 53463, 58590, 64476, 69214, 76693, 83132, 90303, 96766
Offset: 1

Views

Author

R. H. Hardin, May 04 2013

Keywords

Crossrefs

Row 2 of A225258.

Programs

  • Python
    def a(n):
      zn = list(range(n+1))
      prod3 = list(set(i*j*k for i in zn for j in zn[i:] for k in zn[j:]))
      return len(set(a+b for i, a in enumerate(prod3) for b in prod3[i:]))
    print([a(n) for n in range(1, 42)]) # Michael S. Branicky, Mar 12 2021

A225260 Number of distinct values of the sum of 3 products of three 0..n integers.

Original entry on oeis.org

4, 20, 63, 141, 284, 478, 780, 1156, 1667, 2298, 3111, 4012, 5213, 6520, 8063, 9839, 11943, 14184, 16882, 19667, 22953, 26467, 30431, 34509, 39359, 44396, 49878, 55801, 62298, 68881, 76518, 84233, 92751, 101639, 111167, 121017, 132078, 143185, 155102
Offset: 1

Views

Author

R. H. Hardin May 04 2013

Keywords

Comments

Row 3 of A225258

A225261 Number of distinct values of the sum of 4 products of three 0..n integers.

Original entry on oeis.org

5, 28, 90, 205, 409, 694, 1123, 1668, 2396, 3298, 4442, 5741, 7410, 9266, 11443, 13937, 16857, 20031, 23746, 27694, 32236, 37143, 42619, 48390, 55021, 62036, 69617, 77815, 86744, 96000, 106372, 117136, 128823, 141110, 154192, 167871, 182867, 198285
Offset: 1

Views

Author

R. H. Hardin, May 04 2013

Keywords

Crossrefs

Cf. A027426.
Row 4 of A225258.

Programs

  • Python
    from itertools import combinations_with_replacement as mc
    def a(n):
      prods = set(a*b*c for a, b, c in mc(range(n+1), 3))
      return len(set(sum(p) for p in mc(prods, 4)))
    print([a(n) for n in range(1, 11)]) # Michael S. Branicky, May 28 2021

A225262 Number of distinct values of the sum of 5 products of three 0..n integers.

Original entry on oeis.org

6, 36, 117, 269, 534, 910, 1466, 2180, 3125, 4298, 5773, 7469, 9607, 12010, 14818, 18033, 21770, 25863, 30605, 35694, 41497, 47791, 54786, 62214, 70646, 79612, 89300, 99767, 111133, 123000, 136163, 149904, 164760, 180414, 197067, 214527, 233520
Offset: 1

Views

Author

R. H. Hardin May 04 2013

Keywords

Comments

Row 5 of A225258

A225264 Minimum value unattainable as the sum of 2 attained values of a*b*c with a,b,c 0..n integers.

Original entry on oeis.org

3, 7, 23, 23, 71, 71, 289, 311, 311, 311, 479, 479, 1559, 1559, 1559, 1559, 4253, 5637, 7142, 7469, 8843, 10103, 13445, 13445, 15457, 18043, 18191, 18191, 27313, 28442, 32249, 34637, 40367, 43445, 48409, 49957, 57167, 61459, 67513, 69241, 78913, 84533
Offset: 1

Views

Author

R. H. Hardin, May 04 2013

Keywords

Comments

Related to A225258.

Crossrefs

Cf. A225258.

A225265 Minimum value unattainable as the sum of 3 attained values of a*b*c with a,b,c 0..n integers.

Original entry on oeis.org

4, 15, 50, 110, 222, 379, 632, 977, 1372, 1911, 2773, 3325, 4579, 5647, 6949, 8837, 10730, 12421, 15341, 17361, 20609, 23147, 27601, 30529, 35729, 39783, 45565, 50689, 56263, 62647, 70658, 76929, 83926, 93107, 102419, 110029, 122550, 131955, 145096
Offset: 1

Views

Author

R. H. Hardin May 04 2013

Keywords

Comments

related to A225258

A225266 Minimum value unattainable as the sum of 4 attained values of a*b*c with a,b,c 0..n integers.

Original entry on oeis.org

5, 23, 77, 174, 347, 595, 975, 1489, 2101, 2911, 4104, 5053, 6776, 8391, 10324, 12933, 15643, 18637, 22200, 25466, 30206, 34659, 39768, 44905, 51828, 58383, 65422, 73453, 81960, 89647, 100449, 111017, 121480, 134550, 146476, 158737, 173607, 188827
Offset: 1

Views

Author

R. H. Hardin May 04 2013

Keywords

Comments

related to A225258
Showing 1-8 of 8 results.