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A044276
Numbers n such that string 2,7 occurs in the base 9 representation of n but not of n-1.
0
25, 106, 187, 225, 268, 349, 430, 511, 592, 673, 754, 835, 916, 954, 997, 1078, 1159, 1240, 1321, 1402, 1483, 1564, 1645, 1683, 1726, 1807, 1888, 1969, 2025, 2131, 2212, 2293, 2374, 2412, 2455, 2536, 2617, 2698, 2779, 2860
OFFSET
1,1
MATHEMATICA
Select[Range[3000], MemberQ[Partition[IntegerDigits[#, 9], 2, 1], {2, 7}]&&!MemberQ[ Partition[ IntegerDigits[#-1, 9], 2, 1], {2, 7}]&] (* Harvey P. Dale, Sep 30 2011 *)
SequencePosition[Table[If[SequenceCount[IntegerDigits[n, 9], {2, 7}]>0, 1, 0], {n, 3000}], {0, 1}][[;; , 2]] (* Harvey P. Dale, Mar 19 2023 *)
CROSSREFS
Sequence in context: A042222 A379868 A158551 * A044657 A160437 A050589
KEYWORD
nonn,base
STATUS
approved