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 A231964 #22 Feb 16 2025 08:33:20
%S A231964 246,288,290,304,322,324,406,472,516,518,624,626,668,748,766,782,802,
%T A231964 892,894,896,934,964,1044,1078,1146,1148,1160,1246,1254,1256,1312,
%U A231964 1314,1316,1346,1404,1418,1420,1506,1508,1680,1716,1774,1820,1838,1840,1842,1894
%N A231964 Lesser member of untouchable twin pairs, that is, such that a(n) and a(n)+2 are untouchable (A005114).
%C A231964 There are 2673 terms in this sequence when the 8153 terms of A005114, up to 60000, are taken into account.
%C A231964 Note that some numbers come up by pairs like (288,290) or (322,324), corresponding to untouchable triples. Others come up by groups of 3 like (892,894,896) or (1312,1314,1316), corresponding to untouchable quadruplets. For higher n-tuplets, see A231965.
%H A231964 Donovan Johnson, <a href="/A231964/b231964.txt">Table of n, a(n) for n = 1..10000</a>
%H A231964 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/UntouchableNumber.html">Untouchable Number.</a>
%H A231964 Wikipedia, <a href="http://en.wikipedia.org/wiki/Untouchable_number">Untouchable number</a>
%e A231964 246 and 248 are untouchable, so 246 is in this sequence.
%o A231964 (PARI) lista() = {v = readvec("untouchable.log"); for (i=1, #v, vi = v[i]; if (vecsearch(v, vi+2, ), print1(vi, ", ")););} \\ _Michel Marcus_, Nov 16 2013
%Y A231964 Cf. A005114, A231965.
%K A231964 nonn
%O A231964 1,1
%A A231964 _Michel Marcus_, Nov 16 2013