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.

A309760 Even numbers k such that k-p is composite where p is the largest prime <= k.

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%I A309760 #29 Sep 18 2019 01:28:51
%S A309760 122,148,190,208,220,250,292,302,326,346,418,430,476,518,532,538,556,
%T A309760 586,628,640,670,700,718,782,796,806,820,838,848,872,896,902,928,962,
%U A309760 1006,1030,1048,1060,1078,1084,1138,1144,1150,1162,1180,1210,1246,1258,1268,1274
%N A309760 Even numbers k such that k-p is composite where p is the largest prime <= k.
%t A309760 Select[Range[4, 1274, 2], CompositeQ[# - NextPrime[#, -1]] &] (* _Amiram Eldar_, Sep 17 2019 *)
%o A309760 (PARI) is(n) = if(n%2==1 ||n==2, return(0)); my(c = n - precprime(n)); !isprime(c) && c != 1 \\ _David A. Corneth_, Aug 21 2019
%Y A309760 Cf. A007917, A018252, A049711, A025583.
%K A309760 nonn
%O A309760 1,1
%A A309760 _Aaron Schäfers_, Aug 15 2019