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 1-5 of 5 results.

A003350 Numbers that are the sum of 5 positive 5th powers.

Original entry on oeis.org

5, 36, 67, 98, 129, 160, 247, 278, 309, 340, 371, 489, 520, 551, 582, 731, 762, 793, 973, 1004, 1028, 1059, 1090, 1121, 1152, 1215, 1270, 1301, 1332, 1363, 1512, 1543, 1574, 1754, 1785, 1996, 2051, 2082, 2113, 2144, 2293, 2324, 2355, 2535, 2566, 2777, 3074, 3105, 3129
Offset: 1

Views

Author

Keywords

Examples

			From _David A. Corneth_, Aug 03 2020: (Start)
122490 is in the sequence as 122490 = 3^5 + 4^5 + 5^5 + 9^5 + 9^5.
251124 is in the sequence as 251124 = 1^5 + 3^5 + 4^5 + 4^5 + 12^5.
349858 is in the sequence as 349858 = 1^5 + 1^5 + 4^5 + 10^5 + 12^5. (End)
		

Crossrefs

Programs

  • Mathematica
    f[upto_]:=Module[{max=Floor[Power[upto, (5)^-1]],tp},tp=Union[ Total/@ (Tuples[ Range[max],{5}]^5)]; Select[tp,#<=upto&]]; f[2100]  (* Harvey P. Dale, Mar 22 2011 *)

A342686 Numbers that are the sum of five fifth powers in exactly two ways.

Original entry on oeis.org

4097, 51446, 51477, 51688, 52469, 54570, 59221, 68252, 68905, 84213, 110494, 131104, 151445, 212496, 300277, 325174, 325713, 355114, 422135, 422738, 589269, 637418, 794434, 810820, 876734, 876765, 876976, 877757, 879858, 884509, 893540, 909501, 924912, 935782, 976733, 995571, 1037784, 1083457
Offset: 1

Views

Author

David Consiglio, Jr., May 18 2021

Keywords

Comments

This sequence differs from A342685:
13124675 = 1^5 + 9^5 + 10^5 + 20^5 + 25^5
= 2^5 + 5^5 + 12^5 + 23^5 + 23^5
= 16^5 + 19^5 + 20^5 + 20^5 + 20^5,
so 13124675 is in A342685, but is not in this sequence.

Examples

			51477 = 2^5 + 4^5 + 7^5 + 7^5 + 7^5
      = 2^5 + 5^5 + 6^5 + 6^5 + 8^5
so 51477 is a term of this sequence.
		

Crossrefs

Programs

  • Python
    from itertools import combinations_with_replacement as cwr
    from collections import defaultdict
    keep = defaultdict(lambda: 0)
    power_terms = [x**5 for x in range(1, 500)]
    for pos in cwr(power_terms, 5):
        tot = sum(pos)
        keep[tot] += 1
    rets = sorted([k for k, v in keep.items() if v == 2])
    for x in range(len(rets)):
        print(rets[x])

A344190 Numbers that are the sum of five fourth powers in exactly one way.

Original entry on oeis.org

5, 20, 35, 50, 65, 80, 85, 100, 115, 130, 145, 165, 180, 195, 210, 245, 290, 305, 320, 325, 355, 370, 385, 405, 420, 435, 450, 500, 530, 545, 560, 580, 595, 610, 625, 629, 644, 659, 674, 675, 689, 690, 709, 724, 739, 754, 755, 770, 785, 789, 800, 804, 819, 850, 865, 869, 899, 914, 929, 930, 949, 964, 979, 994, 1025, 1040
Offset: 1

Views

Author

David Consiglio, Jr., May 11 2021

Keywords

Comments

Differs from A003339 at term 17 because 260 = 1^4 + 1^4 + 1^4 + 1^4 + 4^4 = 1^4 + 2^4 + 3^4 + 3^4 + 3^4

Examples

			35 is a member of this sequence because 35 = 1^4 + 1^4 + 1^4 + 2^4 + 2^4
		

Crossrefs

Programs

  • Python
    from itertools import combinations_with_replacement as cwr
    from collections import defaultdict
    keep = defaultdict(lambda: 0)
    power_terms = [x**4 for x in range(1,50)]
    for pos in cwr(power_terms,5):
        tot = sum(pos)
        keep[tot] += 1
    rets = sorted([k for k,v in keep.items() if v == 1])
    for x in range(len(rets)):
        print(rets[x])

A344642 Numbers that are the sum of four fifth powers in exactly one way.

Original entry on oeis.org

4, 35, 66, 97, 128, 246, 277, 308, 339, 488, 519, 550, 730, 761, 972, 1027, 1058, 1089, 1120, 1269, 1300, 1331, 1511, 1542, 1753, 2050, 2081, 2112, 2292, 2323, 2534, 3073, 3104, 3128, 3159, 3190, 3221, 3315, 3370, 3401, 3432, 3612, 3643, 3854, 4096, 4151, 4182, 4213, 4393, 4424, 4635, 5174, 5205, 5416, 6197, 6252
Offset: 1

Views

Author

David Consiglio, Jr., May 25 2021

Keywords

Comments

Differs from A003349 at term 270 because 51445 = 4^5 + 8^5 + 8^5 + 8^5 = 6^5 + 7^5 + 7^5 + 9^5

Examples

			66 is a term because 66 = 1^5 + 1^5 + 2^5 + 2^5
		

Crossrefs

Programs

  • Python
    from itertools import combinations_with_replacement as cwr
    from collections import defaultdict
    keep = defaultdict(lambda: 0)
    power_terms = [x**5 for x in range(1, 500)]
    for pos in cwr(power_terms, 4):
        tot = sum(pos)
        keep[tot] += 1
    rets = sorted([k for k, v in keep.items() if v == 1])
    for x in range(len(rets)):
        print(rets[x])

A346356 Numbers that are the sum of six fifth powers in exactly one way.

Original entry on oeis.org

6, 37, 68, 99, 130, 161, 192, 248, 279, 310, 341, 372, 403, 490, 521, 552, 583, 614, 732, 763, 794, 825, 974, 1005, 1029, 1036, 1060, 1091, 1122, 1153, 1184, 1216, 1247, 1271, 1302, 1333, 1364, 1395, 1458, 1513, 1544, 1575, 1606, 1755, 1786, 1817, 1997, 2028
Offset: 1

Views

Author

David Consiglio, Jr., Jul 13 2021

Keywords

Comments

Differs from A003351 at term 93 because 4098 = 1^5 + 3^5 + 3^5 + 3^5 + 3^5 + 5^5 = 1^5 + 1^5 + 4^5 + 4^5 + 4^5 + 4^5.

Examples

			6 is a term because 6 = 1^5 + 1^5 + 1^5 + 1^5 + 1^5 + 1^5.
		

Crossrefs

Programs

  • Python
    from itertools import combinations_with_replacement as cwr
    from collections import defaultdict
    keep = defaultdict(lambda: 0)
    power_terms = [x**5 for x in range(1, 1000)]
    for pos in cwr(power_terms, 6):
        tot = sum(pos)
        keep[tot] += 1
        rets = sorted([k for k, v in keep.items() if v == 1])
        for x in range(len(rets)):
            print(rets[x])
Showing 1-5 of 5 results.