A075359 Sum of the digits of the next n numbers.

1, 5, 15, 25, 20, 39, 49, 53, 72, 91, 113, 141, 160, 137, 102, 121, 161, 207, 253, 203, 168, 223, 290, 354, 202, 287, 369, 388, 293, 393, 502, 362, 444, 571, 440, 531, 649, 509, 672, 655, 659, 813, 670, 881, 441, 505, 473, 537, 556, 605, 633, 697, 692, 801

Offset: 1

Author

Amarnath Murthy, Sep 19 2002

Keywords

• nonn
• base

Examples

			a(5) = digit sum of 11,12,13,14 and 15 = 20.
		

Links

• Harvey P. Dale, Table of n, a(n) for n = 1..1000

Crossrefs

Cf. A037123.

Programs

Mathematica

Total[Flatten[IntegerDigits/@#]]&/@With[{nn=60},TakeList[Range[(nn(nn+1))/2],Range[ nn]]] (* Harvey P. Dale, Jul 11 2023 *)

Formula

a(n) = A037123(n*(n+1)/2)-A037123(n*(n-1)/2). - David Wasserman, Jan 16 2005

Extensions

More terms from David Wasserman, Jan 16 2005