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A044000
Numbers k such that 0 and 5 occur juxtaposed in the base-10 representation of k but not of k+1.
1
50, 105, 150, 205, 250, 305, 350, 405, 450, 509, 550, 605, 650, 705, 750, 805, 850, 905, 950, 1005, 1059, 1105, 1150, 1205, 1250, 1305, 1350, 1405, 1450, 1509, 1550, 1605, 1650, 1705, 1750, 1805, 1850, 1905, 1950, 2005, 2059
OFFSET
1,1
LINKS
MATHEMATICA
With[{j = 0, k = 5}, Position[Partition[Array[Boole[Total@ {SequenceCount[#, {j, k}], SequenceCount[#, {k, j}]} > 0] &@ IntegerDigits[#] &, 2100], 2, 1], {1, 0}][[All, 1]]] (* Michael De Vlieger, Aug 27 2021 *)
CROSSREFS
Sequence in context: A304840 A043220 A039397 * A256631 A250724 A044237
KEYWORD
nonn,base
STATUS
approved