

A262096


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.


3



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, 17, 16, 14, 54, 53, 51, 50, 45, 44, 42, 41, 56, 55, 53, 52, 47, 46, 44, 43, 29, 60, 59, 57, 56, 51, 50, 48, 47, 33, 32, 62, 61, 59, 58, 53, 52, 50, 49, 35, 34, 32
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OFFSET

1,1


COMMENTS

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.


LINKS



EXAMPLE

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; ...
As a triangle, sequence starts:
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, 17, 16, 14;
54, 53, 51, 50, 45, 44, 42, 41;
...


PROG

(PARI) isok(n) = (n==0)  (vecmax(digits(n, 3)) != 2);
lista(nn) = {oks = select(x>isok(x), vector(nn, n, n1)); for (n=2, #oks, for (k=1, n1, print1(2*oks[n]oks[k], ", "); ); ); } \\ Michel Marcus, Sep 12 2015


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AUTHOR



EXTENSIONS



STATUS

approved



