A053019 Let Do(n) = A006566(n) = n-th dodecahedral number. Consider all integer triples (i,j,k), j >= k > 0, with Do(i) = Do(j) + Do(k), ordered by increasing i; sequence gives k values.

46, 142, 290, 1536, 6126, 894, 6106, 14539, 9886, 2020, 21179, 21502, 13052, 15751, 3830, 42370, 62580, 6486, 10150, 56214, 14984, 21150, 368668, 354310, 558467, 28810, 38126, 419690, 1237147, 49260, 1056710, 652670

Offset: 1

Author

Klaus Strassburger (strass(AT)ddfi.uni-duesseldorf.de), Feb 24 2000

Keywords

• nice
• nonn

Comments

i values are A053017 and j values are A053018.

Examples

			Do(179) = 25665020 = 25236484 + 428536 = Do(178) + Do(46);
Do(184) = 27880600 = 15086400 + 12794200 = Do(150) + Do(142).
		

Programs

Mathematica

(* This is just a recomputation of k values, given i values. *)
A053017 = Cases[Import["https://oeis.org/A053017/b053017.txt", "Table"], {, }][[All, 2]];
do[n_] := n*(3*n - 1)*(3*n - 2)/2;
triples = Reap[Module[{s, i, j, k, n, ijk}, s[i_] := Solve[j >= k > 0 && do[i] == do[j] + do[k], {j, k}, Integers]; For[n = 1, n <= Length[A053017], n++, i = A053017[[n]]; ijk = {i, j, k} /. s[i] // First; Print[ijk]; Sow[ijk]]]][[2, 1]];
A053019 = triples[[All, 3]] (* Jean-François Alcover, Feb 17 2015, updated Jul 09 2022 *)

Extensions

More terms from Jon E. Schoenfield, Aug 13 2007

a(27)-a(32) from Donovan Johnson, Aug 15 2010