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.

A028562 Palindromes of form k*(k+6).

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%I A028562 #10 Aug 11 2024 14:41:29
%S A028562 0,7,55,616,19591,76167,515515,749947,7474747,72999927,236799997632,
%T A028562 769437734967,1900289820091,2998954598992,5170703070715,5934592954395,
%U A028562 29175111157192,51175166157115,57154688645175,211106050601112,570608929806075,574823545328475
%N A028562 Palindromes of form k*(k+6).
%H A028562 Michael S. Branicky, <a href="/A028562/b028562.txt">Table of n, a(n) for n = 1..35</a>
%H A028562 P. De Geest, <a href="https://www.worldofnumbers.com/consemor.htm">Palindromic Quasipronics of the form n(n+x)</a>
%F A028562 a(n) = A028561(n) * (A028561(n) + 6). - _Michael S. Branicky_, Jan 25 2022
%o A028562 (Python)
%o A028562 from itertools import count, islice
%o A028562 def ispal(n): s = str(n); return s == s[::-1]
%o A028562 def agen():
%o A028562     for k in count(0):
%o A028562         if ispal(k*(k+6)):
%o A028562             yield k*(k+6)
%o A028562 print(list(islice(agen(), 19))) # _Michael S. Branicky_, Jan 25 2022
%Y A028562 Cf. A028560, A028561.
%K A028562 nonn,base
%O A028562 1,2
%A A028562 _Patrick De Geest_
%E A028562 a(20) and beyond from _Michael S. Branicky_, Jan 25 2022