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A099967 Second column of triangle in A099961. 1
1, 2, 3, 5, 10, 23, 51, 128, 386, 1092, 3370, 12458, 43037, 158638, 691999, 2827035, 12150430, 60980759, 287737037, 1414689552, 8021603122, 42939104470, 237864297110, 1502870474645, 8999347646633, 55484973357830 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Table of n, a(n) for n=0..25.

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: R[0]:=vector(1, 1): for n from 1 to 31 do if n mod 3 = 0 or n mod 3 = 1 then R[n]:=ps(rev(R[n-1])) else R[n]:=pss(rev(R[n-1])) fi od: seq(R[n][2], n=2..31); # Emeric Deutsch, Nov 16 2004

CROSSREFS

Cf. A099961, A099962, A099963.

Sequence in context: A173271 A280019 A063253 * A106531 A101163 A155587

Adjacent sequences:  A099964 A099965 A099966 * A099968 A099969 A099970

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

STATUS

approved

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Last modified March 19 11:29 EDT 2019. Contains 321329 sequences. (Running on oeis4.)