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 A116935 Semiprimes (A001358) which are the concatenation of the numbers 1 through n for some n. 2
 123, 1234, 1234567, 12345678910111213141516171819202122232425262728293031323334 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Next term has 185 digits, and it is thus too large to be included. It is equal to the concatenation of the first 97 integers. - Giovanni Resta, Jun 15 2016 LINKS Table of n, a(n) for n=1..4. FORMULA {A007908} intersect {A001358}. EXAMPLE a(1) = 123 = 3 * 41. a(2) = 1234 = 2 * 617. a(3) = 1234567 = 127 * 9721. a(4) = 2 * 6172839455055606570758085909601061116212631364146515661667. CROSSREFS Cf. A001358, A007908. Sequence in context: A233119 A167231 A174173 * A265983 A103504 A324627 Adjacent sequences: A116932 A116933 A116934 * A116936 A116937 A116938 KEYWORD base,nonn,less AUTHOR Jonathan Vos Post, Mar 20 2006 STATUS approved

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Last modified May 24 07:02 EDT 2024. Contains 372772 sequences. (Running on oeis4.)