OFFSET
1,5
EXAMPLE
Triangle begins:
1
1 1
1 3 1
1 5 2
1 9 7 2
1 11 8 2
1 17 19 10 2
1 21 25 14 3
1 27 37 24 6
1 31 42 26 6
1 41 73 68 32 6
1 45 79 72 33 6
1 57 124 151 105 39 6
1 63 138 167 114 41 6
1 71 159 192 128 44 6
1 79 183 228 157 56 8
MATHEMATICA
Table[Length[Select[Subsets[Range[n], {k}], CoprimeQ@@#&]], {n, 16}, {k, PrimePi[n]+1}]
CROSSREFS
KEYWORD
nonn,tabf
AUTHOR
Gus Wiseman, Jan 08 2019
STATUS
approved