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A117597
Padovan numbers for which the sum of the digits is also a Padovan number.
1
0, 1, 2, 3, 4, 5, 7, 9, 12, 16, 21, 151, 200, 351, 4410, 73396, 170625, 922111, 1221537, 1618192, 2143648, 35676949, 62608681, 1380359512, 2422362079, 4250949112, 7459895657, 93722435101, 164471408185, 217878227876, 2066337330754
OFFSET
0,3
LINKS
EXAMPLE
The Padovan number 73396 is in the sequence because also 28 (=7+3+3+9+6) is a Padovan number.
MAPLE
p[0]:=1: p[1]:=1: p[2]:=1: for n from 3 to 170 do p[n]:=p[n-2]+p[n-3] od: P:=[seq(p[n], n=0..170)]: a:=proc(n) local nn, sod: nn:=convert(P[n], base, 10): sod:=add(nn[j], j=1..nops(nn)): if member(sod, P)=true then P[n] else fi end: 0, 1, seq(a(n), n=5..nops(P)); # Emeric Deutsch, Apr 16 2006
MATHEMATICA
Join[{0}, With[{pads=LinearRecurrence[{0, 1, 1}, {1, 1, 1}, 150]}, Union[ Select[ pads, MemberQ[pads, Total[IntegerDigits[#]]]&]]]] (* Harvey P. Dale, Sep 05 2012 *)
CROSSREFS
Cf. A000931.
Sequence in context: A164001 A117598 A120149 * A241336 A233522 A112639
KEYWORD
nonn,base
AUTHOR
Luc Stevens (lms022(AT)yahoo.com), Apr 05 2006
EXTENSIONS
More terms from Emeric Deutsch, Apr 16 2006
STATUS
approved