OFFSET
1,1
COMMENTS
Previous name was: 3 people at a party are saying Hello to each other. Person 3 says Hello Hello Hello. Person 1 counts the times Hello has been said and says Hello that number of times. Person 2 says Hello a number of times equal to 2 * the sum of Hello's; then it is Person 3's turn again. Sequence gives the number of Hello's said.
LINKS
FORMULA
G.f.: 3*x*(1-x)*(1+2*x+6*x^2)/(1-24*x^3). [Colin Barker, Jun 07 2012]
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Jon Perry, Oct 15 2002
STATUS
approved