A104618 - OEIS

A104618

Write the natural numbers in base 15 in a triangle with k digits in the k-th row, as shown below. Sequence gives the leading diagonal.

%I #2 Mar 30 2012 17:31:12

%S 1,3,6,10,1,1,6,10,2,2,10,1,3,4,7,0,5,6,12,7,8,8,10,7,11,12,1,0,1,1,1,

%T 1,1,3,1,1,5,1,1,8,1,1,11,1,1,14,2,2,2,2,2,5,2,2,9,2,2,13,2,3,2,3,3,6,

%U 3,3,10,3,3,0,4,4,5,4,4,10,4,4,0,5,5,5,5,5,11,5,6,2,6,6,8,6,6,14,7,7,5,7,7

%N Write the natural numbers in base 15 in a triangle with k digits in the k-th row, as shown below. Sequence gives the leading diagonal.

%C 1

%C 23

%C 456

%C 789A

%C BCDE1

%C 011121...

%t t = Flatten[ IntegerDigits[ Range[1900], 15]]; t[[Table[n(n + 1)/2, {n, 100}]]]

%Y Cf. A104606, A104607, A104608, A104609, A104610, A104611, A104612, A104613, A091425, A104614, A104615, A104616, A104617, A104619, A104620.

%K base,nonn

%O 1,2

%A _Robert G. Wilson v_, Mar 16 2005