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A099968 Second column of triangle in A099964. 2
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 (list; graph; refs; listen; history; text; internal format)
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); (Deutsch)

PROG

(Haskell)

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

CROSSREFS

Cf. A099964, A099965, A099966.

Sequence in context: A006444 A032047 A032065 * A010357 A190166 A238823

Adjacent sequences:  A099965 A099966 A099967 * A099969 A099970 A099971

KEYWORD

nonn,easy

AUTHOR

N. J. A. Sloane, Nov 13 2004, following a suggestion made by Douglas G. Rogers, Mar 10, 2003

EXTENSIONS

More terms from Emeric Deutsch, Nov 16 2004

Offset corrected by Reinhard Zumkeller, May 02 2012

STATUS

approved

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Last modified December 9 20:00 EST 2016. Contains 278986 sequences.