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A082247
Multiples of 7 that are concatenation of 7 consecutive natural numbers.
5
3456789, 13141516171819, 20212223242526, 27282930313233, 34353637383940, 41424344454647, 48495051525354, 55565758596061, 62636465666768, 69707172737475, 76777879808182, 83848586878889, 90919293949596, 102103104105106107108, 109110111112113114115
OFFSET
1,1
COMMENTS
From 2nd terms onwards it is observed that if a(r) ends in k then a(r+1) begins with k+1. This is true up to the term 90919293949596. (Why?)
LINKS
MATHEMATICA
Select[FromDigits[Flatten[IntegerDigits[#]]]&/@Partition[Range[100], 7, 1], Divisible[ #, 7]&] (* Harvey P. Dale, May 18 2021 *)
CROSSREFS
KEYWORD
base,easy,nonn
AUTHOR
Amarnath Murthy, Apr 11 2003
STATUS
approved