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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
FORMULA
log a(n) grows like a constant times phi^n, where 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 -> oo} 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).
MATHEMATICA
NestList[Flatten@ MapIndexed[ConstantArray[First[#2], #1] &, #] &, {1, 1}, 8][[All, -1]] (* Michael De Vlieger, Dec 16 2021 *)
CROSSREFS
Sequence in context: A127166 A103596 A005426 * A089541 A065843 A111264
Adjacent sequences: A014641 A014642 A014643 * A014645 A014646 A014647
KEYWORD
nonn,nice
AUTHOR
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 July 23 10:24 EDT 2024. Contains 374547 sequences. (Running on oeis4.)