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.

A344927 Numbers that are the sum of four fourth powers in exactly nine ways.

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%I A344927 #6 Jul 31 2021 22:12:24
%S A344927 328118259,385202034,395613234,489597858,625839858,641398338,
%T A344927 674511618,693239634,699598578,722302434,779889314,780278643,
%U A344927 782999714,791204514,792005379,797405714,797935698,805299699,815120658,822938754,851527314,857962914,870861618
%N A344927 Numbers that are the sum of four fourth powers in exactly nine ways.
%C A344927 Differs from A344926 at term 5 because 328118259 is a term because 328118259 = 2^4 + 77^4 + 109^4 + 111^4  = 8^4 + 79^4 + 93^4 + 121^4  = 18^4 + 79^4 + 97^4 + 119^4  = 21^4 + 77^4 + 98^4 + 119^4  = 27^4 + 77^4 + 94^4 + 121^4  = 34^4 + 77^4 + 89^4 + 123^4  = 46^4 + 57^4 + 103^4 + 119^4  = 49^4 + 77^4 + 77^4 + 126^4  = 61^4 + 66^4 + 77^4 + 127^4.
%H A344927 David Consiglio, Jr., <a href="/A344927/b344927.txt">Table of n, a(n) for n = 1..64</a>
%e A344927 328118259 is a term because 328118259 = 2^4 + 77^4 + 109^4 + 111^4  = 8^4 + 79^4 + 93^4 + 121^4  = 18^4 + 79^4 + 97^4 + 119^4  = 21^4 + 77^4 + 98^4 + 119^4  = 27^4 + 77^4 + 94^4 + 121^4  = 34^4 + 77^4 + 89^4 + 123^4  = 46^4 + 57^4 + 103^4 + 119^4  = 49^4 + 77^4 + 77^4 + 126^4  = 61^4 + 66^4 + 77^4 + 127^4.
%o A344927 (Python)
%o A344927 from itertools import combinations_with_replacement as cwr
%o A344927 from collections import defaultdict
%o A344927 keep = defaultdict(lambda: 0)
%o A344927 power_terms = [x**4 for x in range(1, 1000)]
%o A344927 for pos in cwr(power_terms, 4):
%o A344927     tot = sum(pos)
%o A344927     keep[tot] += 1
%o A344927 rets = sorted([k for k, v in keep.items() if v == 9])
%o A344927 for x in range(len(rets)):
%o A344927     print(rets[x])
%Y A344927 Cf. A341892, A344751, A344925, A344926, A344929, A345154.
%K A344927 nonn
%O A344927 1,1
%A A344927 _David Consiglio, Jr._, Jun 02 2021