A262096 - OEIS

%I #55 May 09 2021 02:16:54

%S 2,6,5,8,7,5,18,17,15,14,20,19,17,16,11,24,23,21,20,15,14,26,25,23,22,

%T 17,16,14,54,53,51,50,45,44,42,41,56,55,53,52,47,46,44,43,29,60,59,57,

%U 56,51,50,48,47,33,32,62,61,59,58,53,52,50,49,35,34,32

%N Triangle read by rows: numbers c from the set of arithmetic triples a < b < c (three numbers in arithmetic progression) where a and b are terms of A005836.

%C The first term in each row of the triangle is a term of A005823; these are also the local maxima. From this term until the next row, the first differences are A236313.

%H Max Barrentine, <a href="/A262096/b262096.txt">Table of n, a(n) for n = 1..2016</a>

%e Each term is generated from arithmetic sequences started from pairs of terms from A005836. The order is according to the arithmetic triples 0, 1, a(1)=2; 0, 3, a(2)=6; 1, 3, a(3)=5; 0, 4, a(4)=8; 1, 4, a(5)=7; 3, 4, a(6)=5; ...

%e As a triangle, sequence starts:

%e    2;

%e    6,  5;

%e    8,  7,  5;

%e   18, 17, 15, 14;

%e   20, 19, 17, 16, 11;

%e   24, 23, 21, 20, 15, 14;

%e   26, 25, 23, 22, 17, 16, 14;

%e   54, 53, 51, 50, 45, 44, 42, 41;

%e   ...

%o (PARI) isok(n) = (n==0) || (vecmax(digits(n, 3)) != 2);

%o lista(nn) = {oks = select(x->isok(x), vector(nn, n, n-1)); for (n=2, #oks, for (k=1, n-1, print1(2*oks[n]-oks[k], ", ");););} \\ _Michel Marcus_, Sep 12 2015

%Y Cf. A005823, A005836, A074940, A236313, A262097, A262256.

%K nonn,look,tabl,base

%O 1,1

%A _Max Barrentine_, Sep 10 2015

%E Name corrected by _Max Barrentine_, May 24 2016