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A014644 Form array starting with {1,1}; then i-th term in a row gives number of i's in next row; sequence is formed from final term in each row. 5
1, 2, 2, 3, 5, 11, 38, 272, 6474, 1090483, 4363282578, 2940715000315189, 7930047000157075949085439, 14412592242471457956514645440241289655074, 70636608026754077888330819116433040562582634705380432362008848092 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..15.

FORMULA

log a(n) grows like constant times phi^n, phi = Golden ratio (Colin Mallows).

a(n) converges to a(n-2)*a(n-1)*phi (within 6 decimals for a[15]) - Johan Claes, Oct 02 2005

Limit n --> infty a(n+2)/a(n+1)/a(n)=1/Phi. - Benoit Cloitre, Oct 13 2005

EXAMPLE

a[5]=5 because 5 is the last number of the 5th row of A014643 (1,2,2,3,3,4,4,4,5,5,5)

CROSSREFS

Cf. A014643, A011784.

Sequence in context: A127166 A103596 A005426 * A089541 A065843 A111264

Adjacent sequences:  A014641 A014642 A014643 * A014645 A014646 A014647

KEYWORD

nonn,nice

AUTHOR

N. J. A. Sloane.

EXTENSIONS

a(1)..a(11) computed by Colin Mallows.

a(12)..a(15) computed by Johan Claes Oct 02 2005

STATUS

approved

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Last modified June 19 05:18 EDT 2021. Contains 345125 sequences. (Running on oeis4.)