A099968 Second column of triangle in A099964.

1, 2, 3, 6, 14, 31, 78, 235, 665, 1926, 5886, 21832, 75333, 266377, 933842, 3422282, 14954936, 61055379, 254751651, 1054728818, 4378056288, 18699691530, 94021272519, 443332334411, 2132051480643, 10181045388314, 48729093879838

Offset

1,2

Links

Reinhard Zumkeller, Table of n, a(n) for n = 1..750

Maple

with(linalg):rev:=proc(a) local n, p; n:=vectdim(a): p:=i->a[n+1-i]: vector(n, p) end: ps:=proc(a) local n, q; n:=vectdim(a): q:=i->sum(a[j], j=1..i): vector(n, q) end: pss:=proc(a) local n, q; n:=vectdim(a): q:=proc(i) if i<=n then sum(a[j], j=1..i) else sum(a[j], j=1..n) fi end: vector(n+1, q) end: tr:={seq(n*(n+1)/2, n=1..30)}: R[0]:=vector(1, 1): for n from 1 to 30 do if member(n, tr)=false then R[n]:=ps(rev(R[n-1])) else R[n]:=pss(rev(R[n-1])) fi od: seq(R[n][2], n=1..30); # Emeric Deutsch, Nov 16 2004

Prog

(Haskell)
a099968 = flip a099964 1 -- Reinhard Zumkeller, May 02 2012

Crossrefs

Cf. A099964, A099965, A099966.

Sequence in context: A032047 A032065 A307231 * A291401 A331875 A010357

Adjacent sequences: A099965 A099966 A099967 * A099969 A099970 A099971

Keyword

nonn,easy

Author

N. J. A. Sloane, Nov 13 2004

Extensions

More terms from Emeric Deutsch, Nov 16 2004

Offset corrected by Reinhard Zumkeller, May 02 2012

Status

approved