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A222173
Number of pentagons added at n-th stage to the structure of A222172.
3
0, 1, 1, 1, 2, 3, 2, 1, 2, 4, 4, 3, 5, 7, 4, 1, 2, 4, 6, 8
OFFSET
0,5
COMMENTS
Essentially the first differences of A222172.
Also number of P-toothpicks added at n-th stage to the P-toothpick structure of A222172.
First differs from A152978 at a(9).
FORMULA
a(n) = A222181(n+2)/10 = A222177(n+1)/2, n >= 1.
EXAMPLE
Apparently this is an irregular triangle:
0;
1, 1;
1, 2, 3, 2;
1, 2, 4, 4, 3, 5, 7, 4;
1, 2, 4, 6, 8,...
CROSSREFS
KEYWORD
nonn,tabf,more
AUTHOR
Omar E. Pol, Mar 21 2013
STATUS
approved