A102856 Sum of 1 or 2 distinct tetrahedral numbers.

0, 1, 4, 5, 10, 11, 14, 20, 21, 24, 30, 35, 36, 39, 45, 55, 56, 57, 60, 66, 76, 84, 85, 88, 91, 94, 104, 119, 120, 121, 124, 130, 140, 155, 165, 166, 169, 175, 176, 185, 200, 204, 220, 221, 224, 230, 240, 249, 255, 276, 285, 286, 287, 290, 296, 304, 306

Offset: 1

Author

Jud McCranie, Mar 01 2005

Keywords

• nonn

Links

• Robert Israel, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A000292 (subsequence), A010329, A104246, A102795-A102800, A102802-A102806, A102855, A102857, A102858, A334013.

Cf. A102801 (sums if 2 distinct positive)

Programs

Maple

N:= 1000: # for terms <= N
R:= 0:
for i from 1 do
  ti:= i*(i+1)*(i+2)/6;
  if ti > N then break fi;
  for j from 0 to i-1 do
     v:= ti + j*(j+1)*(j+2)/6;
     if v > N then break fi;
     R:= R, v;
  od;
od:
sort(convert({R},list)); # Robert Israel, Jan 16 2024

Mathematica

Module[{nn=12, tetra}, tetra=Table[(n(n+1)(n+2))/6, {n, nn}]; Union[ Total/@ Subsets[tetra, 2]]] (* James C. McMahon, Jan 12 2024 *)

Extensions

a(1) = 0 prepended by James C. McMahon, Jan 15 2024