A004160 Sum of digits of the n-th tetrahedral number.

1, 4, 1, 2, 8, 11, 12, 3, 12, 4, 16, 13, 14, 11, 14, 15, 24, 6, 7, 10, 16, 8, 5, 8, 18, 18, 18, 10, 22, 19, 20, 26, 20, 12, 21, 21, 22, 25, 13, 14, 11, 14, 15, 15, 15, 25, 19, 16, 17, 5, 17, 18, 18, 18, 19, 22, 19, 11, 26, 20, 21, 21, 21, 22, 25, 13, 23, 20, 23, 24, 24, 24, 25, 10, 16, 26

Offset

1,2

Links

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

Formula

a(n) = A007953(A000292(n)). - Michel Marcus, Dec 19 2016

Mathematica

Total[IntegerDigits[#]]&/@Table[(n(n+1)(n+2))/6, {n, 80}] (* Harvey P. Dale, Jul 31 2013 *)

Prog

(PARI) a(n)=sumdigits(n*(n+1)*(n+2)/6) \\ Charles R Greathouse IV, Dec 19 2016

Crossrefs

Cf. A000292, A007953.

Sequence in context: A081454 A133883 A279816 * A128077 A128078 A331152

Adjacent sequences: A004157 A004158 A004159 * A004161 A004162 A004163

Keyword

nonn,base,easy

Author

N. J. A. Sloane

Status

approved