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A117766
Fibonacci numbers for which the sum of the digits is a Lucas number.
1
1, 3, 13, 21, 34, 610, 196418, 1134903170, 20365011074, 15635695580168194910579363790217849593217, 1049252690665646467530632231274619718410203796555123147644873726135009824265250
OFFSET
0,2
COMMENTS
The next term has 108 digits. - Harvey P. Dale, Apr 08 2018
EXAMPLE
196418 is in the sequence because (1) it is a Fibonacci number and (2)the sum of its digits 1+9+6+4+1+8=29 is a Lucas number.
MAPLE
with(combinat): L[1]:=1:L[2]:=3: for m from 3 to 30 do L[m]:=L[m-1]+L[m-2] od: LL:=[seq(L[m], m=1..30)]: a:=proc(n) local ff, sod: ff:=convert(fibonacci(n), base, 10): sod:=add(ff[j], j=1..nops(ff)): if member(sod, LL)=true then fibonacci(n) else fi end: seq(a(n), n=2..450); # Emeric Deutsch, Apr 16 2006
MATHEMATICA
Module[{nn=600, luc}, luc=LucasL[Range[nn]]; Select[Fibonacci[ Range[ 2, nn]], MemberQ[luc, Total[ IntegerDigits[#]]]&]] (* Harvey P. Dale, Apr 08 2018 *)
CROSSREFS
Sequence in context: A145024 A055059 A050903 * A243162 A147351 A147097
KEYWORD
base,nonn
AUTHOR
Luc Stevens (lms022(AT)yahoo.com), Apr 15 2006
EXTENSIONS
Corrected and extended by Emeric Deutsch, Apr 16 2006
STATUS
approved