OFFSET
1,2
LINKS
Harvey P. Dale, Table of n, a(n) for n = 1..1000
EXAMPLE
Triangle begins:
1;
2, 3, 4;
5, 6, 7, 8, 9;
12, 13, 14, 15, 16, 17, 18;
27, 28, 29, 30, 31, 32, 33, 34, 35;
58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68;
...
Written as an isosceles triangle the sequence begins:
. 1;
. 2, 3, 4;
. 5, 6, 7, 8, 9;
. 12, 13, 14, 15, 16, 17, 18;
. 27, 28, 29, 30, 31, 32, 33, 34, 35;
. 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68;
..
MATHEMATICA
Table[2^n-n+k-1, {n, 10}, {k, 2n-1}]//Flatten (* Harvey P. Dale, Nov 27 2021 *)
CROSSREFS
KEYWORD
nonn,tabf
AUTHOR
Miquel Cerda, Sep 27 2016
EXTENSIONS
Definition from Omar E. Pol, Sep 28 2016
STATUS
approved