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A038526
Concatenation of prime factors of n-th Fibonacci number.
3
2, 3, 5, 222, 13, 37, 217, 511, 89, 222233, 233, 1329, 2561, 3747, 1597, 2221719, 37113, 351141, 213421, 89199, 28657, 2222233723, 553001, 233521, 21753109, 31329281, 514229, 2225113161, 5572417, 37472207, 28919801, 15973571, 513141961, 22223331719107, 731492221
OFFSET
3,1
LINKS
FORMULA
a(n) = A037276(A000045(n)). - R. J. Mathar, Oct 12 2007
MAPLE
A055642 := proc(n) if n =0 then 1 ; else ilog10(n)+1 ; fi ; end: catDigs := proc(L) local a, k, i ; a := 0 ; for i from 1 to nops(L) do a := a*10^A055642(L[i])+L[i] ; od ; end: A037276 := proc(n) local L, i, ifs, j ; if n = 1 then 0 else ifs := ifactors(n)[2] ; L := [] ; for i in ifs do for j from 1 to op(2, i) do L := [op(L), op(1, i)] ; od: od: catDigs(L) ; fi ; end: A038526 := proc(n) A037276(combinat[fibonacci](n)) ; end: seq(A038526(n), n=3..20) ; # R. J. Mathar, Oct 12 2007
# second Maple program:
F:= n-> (<<0|1>, <1|1>>^n)[1, 2]:
a:= n-> parse(cat(sort(map(i-> i[1]$i[2], ifactors(F(n))[2]))[])):
seq(a(n), n=3..40); # Alois P. Heinz, Aug 17 2018
CROSSREFS
Sequence in context: A041655 A082520 A062597 * A082755 A042067 A333803
KEYWORD
nonn,base
AUTHOR
EXTENSIONS
Edited by Charles R Greathouse IV, Apr 27 2010
STATUS
approved