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A044377
Numbers n such that string 4,5 occurs in the base 10 representation of n but not of n-1.
1
45, 145, 245, 345, 445, 450, 545, 645, 745, 845, 945, 1045, 1145, 1245, 1345, 1445, 1450, 1545, 1645, 1745, 1845, 1945, 2045, 2145, 2245, 2345, 2445, 2450, 2545, 2645, 2745, 2845, 2945, 3045, 3145, 3245, 3345, 3445, 3450
OFFSET
1,1
LINKS
MATHEMATICA
Flatten[Position[Partition[If[MemberQ[Partition[IntegerDigits[#], 2, 1], {4, 5}], 1, 0]&/@Range[3500], 2, 1], {0, 1}]]+1 (* Harvey P. Dale, Aug 14 2014 *)
CROSSREFS
Sequence in context: A373609 A336507 A156370 * A044758 A053743 A347874
KEYWORD
nonn,base
STATUS
approved