|
|
A101098
|
|
a(1)=1; thereafter, a(n+1) = 20*n^3 + 10*n.
|
|
6
|
|
|
1, 30, 180, 570, 1320, 2550, 4380, 6930, 10320, 14670, 20100, 26730, 34680, 44070, 55020, 67650, 82080, 98430, 116820, 137370, 160200, 185430, 213180, 243570, 276720, 312750, 351780, 393930, 439320, 488070, 540300, 596130, 655680, 719070, 786420, 857850
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
1,2
|
|
COMMENTS
|
Shells (nexus numbers) of shells of the fifth powers (A000584).
|
|
LINKS
|
|
|
FORMULA
|
G.f.: x + 30*x^2*(1+x)^2/(1-x)^4. (End)
|
|
MAPLE
|
a:=`if`(n=1, 1, 20*n^3+10*n): 1, seq(a(n), n=1..35); # Muniru A Asiru, Dec 02 2018
|
|
MATHEMATICA
|
|
|
PROG
|
(PARI) my(x='x+O('x^50)); Vec(x + 30*x^2*(1+x)^2/(1-x)^4) \\ G. C. Greubel, Dec 01 2018
(Magma) [n le 1 select 1 else 10*(n - 1)*(2*(n - 1)^2 + 1): n in [1..50]]; // G. C. Greubel, Dec 01 2018
(Sage) s=(x + 30*x^2*(1+x)^2/(1-x)^4).series(x, 50); s.coefficients(x, sparse=False) # G. C. Greubel, Dec 01 2018
(GAP) Concatenation([1], List([1..35], n->20*n^3+10*n)); # Muniru A Asiru, Dec 02 2018
|
|
CROSSREFS
|
|
|
KEYWORD
|
easy,nonn
|
|
AUTHOR
|
Cecilia Rossiter (cecilia(AT)noticingnumbers.net), Dec 15 2004
|
|
EXTENSIONS
|
|
|
STATUS
|
approved
|
|
|
|