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A079480
a(1) = 1; a(2) = 2; a(n) = LS(a(n-1)) + LS(a(n-2)) if n > 2, where LS(m) = the "Look and Say" description (A045918) of m.
0
1, 2, 23, 1225, 113428, 2113253433, 1221133328272641, 112221332439252927292834, 2132112312141319233733522435243624342725, 121113122112131112111411131119124449343834282634242925352431253324352529
OFFSET
1,2
EXAMPLE
E.g. a(7) = LS(a(6))+LS(a(5)). LS(a(6)) = LS(2113253433) = 1221131215131423, LS(a(5)) = LS(113428) = 2113141218 -> a(7) = 1221133328272641
MATHEMATICA
RunLengthEncode[x_List] := (Through[{First, Length}[ #1]] &) /@ Split[x]; LS[n_] := FromDigits[ Reverse[ Flatten[ RunLengthEncode[ Reverse[ IntegerDigits[n]]]]]]; a[1] = 1; a[2] = 2; a[n_] := a[n] = LS[a[n - 1]] + LS[a[n - 2]]; Table[a[n], {n, 1, 10}]
CROSSREFS
Sequence in context: A098633 A015211 A266992 * A239398 A239811 A082963
KEYWORD
base,nonn
AUTHOR
Joseph L. Pe, Jan 15 2003
EXTENSIONS
More terms from Mark Hudson (mrmarkhudson(AT)hotmail.com), Jan 24 2003
Corrected and edited by Robert G. Wilson v, Jan 27 2003
STATUS
approved