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A044405
Numbers n such that string 7,3 occurs in the base 10 representation of n but not of n-1.
0
73, 173, 273, 373, 473, 573, 673, 730, 773, 873, 973, 1073, 1173, 1273, 1373, 1473, 1573, 1673, 1730, 1773, 1873, 1973, 2073, 2173, 2273, 2373, 2473, 2573, 2673, 2730, 2773, 2873, 2973, 3073, 3173, 3273, 3373, 3473, 3573
OFFSET
1,1
MATHEMATICA
SequencePosition[Table[If[SequenceCount[IntegerDigits[n], {7, 3}]>0, 1, 0], {n, 4000}], {0, 1}][[All, 2]] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Mar 25 2021 *)
CROSSREFS
Sequence in context: A078856 A142326 A142377 * A044786 A244774 A142550
KEYWORD
nonn,base
STATUS
approved