A162609 Triangle read by rows in which row n lists n terms, starting with 1, with gaps = n-2 between successive terms.
1, 1, 1, 1, 2, 3, 1, 3, 5, 7, 1, 4, 7, 10, 13, 1, 5, 9, 13, 17, 21, 1, 6, 11, 16, 21, 26, 31, 1, 7, 13, 19, 25, 31, 37, 43, 1, 8, 15, 22, 29, 36, 43, 50, 57, 1, 9, 17, 25, 33, 41, 49, 57, 65, 73, 1, 10, 19, 28, 37, 46, 55, 64, 73, 82, 91, 1, 11, 21, 31, 41, 51, 61, 71, 81
Offset: 1
Examples
Triangle begins: 1; 1, 1; 1, 2, 3; 1, 3, 5, 7; 1, 4, 7, 10, 13; 1, 5, 9, 13, 17, 21; 1, 6, 11, 16, 21, 26, 31;
Crossrefs
Programs
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Mathematica
Table[NestList[#+(n-2)&,1,n-1],{n,20}]//Flatten (* Harvey P. Dale, Oct 23 2017 *)
Formula
T(n,n) = A002061(n-1).
T(n,k) = A076110(n-1,k) = 1+(n-2)*(k-1). - R. J. Mathar, Mar 30 2023
Comments