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.
%I A309325 #9 Jun 24 2022 04:45:22 %S A309325 1,3,5,7,9,11,13,15,17,20,33,55,77,99,121,143,165,187,200,212,232,252, %T A309325 272,292,312,332,352,372,393,414,434,454,474,494,514,534,554,574,595, %U A309325 616,636,656,676,696,716,736,756,776,797,818,838,858,878,898,918,938,958,978 %N A309325 Numbers that are the sum of two successive palindromes. %H A309325 <a href="/index/Pac#palindromes">Index entries for sequences related to palindromes</a> %F A309325 a(n) = A002113(n) + A002113(n+1). %t A309325 Total /@ Partition[Select[Range[0, 500], PalindromeQ], 2, 1] %o A309325 (Python) %o A309325 from itertools import chain, count, islice %o A309325 def A309325_gen(): # generator of terms %o A309325 c = 0 %o A309325 for a in chain.from_iterable(chain((int((s:=str(d))+s[-2::-1]) for d in range(10**l,10**(l+1))), (int((s:=str(d))+s[::-1]) for d in range(10**l,10**(l+1)))) for l in count(0)): %o A309325 yield c+(c:=a) %o A309325 A309325_list = list(islice(A309325_gen(),20)) # _Chai Wah Wu_, Jun 23 2022 %Y A309325 Cf. A002113, A046489, A046497, A260255, A261906. %K A309325 nonn,base %O A309325 1,2 %A A309325 _Ilya Gutkovskiy_, Jul 23 2019