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A118179
Numbers which occur only once in A005229.
1
2, 4, 5, 8, 9, 11, 13, 14, 15, 18, 21, 22, 23, 25, 27, 28, 31, 32, 33, 34, 35, 38, 40, 41, 42, 44, 47, 48, 49, 50, 51, 52, 55, 56, 57, 60, 61, 62, 65, 67, 68, 70, 71, 72, 73, 74, 75, 76, 79, 82, 83, 84, 86, 88, 89, 90, 91, 96, 98, 99, 100, 101, 103, 104, 105, 106, 107, 108
OFFSET
1,1
EXAMPLE
1, 3, 6 and 7 occur twice in A005229, so these numbers are not in the sequence.
MATHEMATICA
terms = 70; Clear[b, f]; b[1] = b[2] = 1; b[n_] := b[n] = b[b[n - 2]] + b[n - b[n - 2]]; f[max_] := f[max] = PadRight[Select[Tally[Array[b, max]], #[[2]] == 1 &][[All, 1]], terms]; f[max = terms]; f[max = max + terms]; While[f[max] != f[max - terms], max = max + terms]; A118179 = f[max](* Jean-François Alcover, Oct 12 2017 *)
PROG
(PARI) {m=156; v=vector(m); v[1]=1; v[2]=1; for(n=3, m, v[n]=v[v[n-2]]+v[n-v[n-2]]); i=1; k=1; while(i<=m, c=0; while(i<=m&&v[i]==k, c++; i++); if(i<=m&&c==1, print1(k, ", ")); k++)}
CROSSREFS
KEYWORD
nonn
AUTHOR
Klaus Brockhaus, Apr 13 2006
STATUS
approved