1,2

For this particular case a(1..2)=1, 2 the sequence is complete with the last term a(24)=7272.

{a(n-2), a(n-1),a(n),c=a(n)+a(n-1)+a(n-2)}

{1,2,3,6}

{2,3,4,9}

{3,4,5,12}

{4,5,7,16}

{5,7,8,20}

{7,8,9,24}

{8,9,10,27}

{9,10,25,44}

{10,25,33,68}

{25,33,40,98}

{33,40,55,128}

{40,55,73,168}

{55,73,81,209}

{73,81,90,244}

{81,90,262,433}

{90,262,433,785}

{262,433,880,1575}

{433,880,959,2272}

{880,959,2272,4111}

{959,2272,3380,6611}

{2272,3380,5459,11111}

{3380,5459,7272,16111}.

ss={1, 2}; a=1; b=2; ia=IntegerDigits[a]; ib=IntegerDigits[b]; Do[ic=IntegerDigits[c]; isu=IntegerDigits[su=a+b+c]; If[Intersection[ic, ia]==Intersection[ic, ib]==Intersection[ic, isu]==Intersection[ia, isu]==Intersection[ib, isu]=={}, Print[{a, b, c, su}]; AppendTo[ss, c]; a=b; b=c; ia=ib; ib=ic], {c, 3, 100000}]; ss

Cf. A166461.

Sequence in context: A330220 A039169 A388968 * A383279 A039263 A344881

Adjacent sequences: A156065 A156066 A156067 * A156069 A156070 A156071

base,fini,full,nonn

Zak Seidov, Oct 23 2009

approved