A053018 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 j values.

178, 150, 2012, 4840, 7773, 8904, 17403, 22363, 24699, 26200, 21916, 22250, 37022, 39223, 61190, 62899, 102450, 123108, 223132, 269966, 374384, 591930, 554636, 636031, 743699, 892780, 1295888, 1468290, 1395491, 1822152, 1859152, 1957822

Offset

1,1

Comments

i values are A053017 and k values are A053019.

Links

Table of n, a(n) for n=1..32.

Example

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

Mathematica

(* This is just a recomputation of j 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]];
A053018 = triples[[All, 2]] (* Jean-François Alcover, Feb 17 2015, updated Jul 09 2022 *)

Crossrefs

Sequence in context: A189910 A189904 A189160 * A046436 A114081 A217037

Adjacent sequences: A053015 A053016 A053017 * A053019 A053020 A053021

Keyword

nice,nonn

Author

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

Extensions

More terms from Jon E. Schoenfield, Aug 13 2007

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

Status

approved