A066553 Let N = 1357911131517192123252729313335373941434547495153555759616365676971..., the concatenation of the odd numbers. a(n) is the n-digit number formed from the digits of N starting from the {n(n-1)/2 +1}th digit. Omit any leading zeros.
1, 35, 791, 1131, 51719, 212325, 2729313, 33537394, 143454749, 5153555759, 61636567697, 173757779818, 3858789919395, 97991011031051, 71091111131151, 1711912112312512, 71291311331351371, 391411431451471491
Offset: 1
Links
- Harvey P. Dale, Table of n, a(n) for n = 1..1000
Programs
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Mathematica
With[{nn=20},FromDigits/@TakeList[Flatten[IntegerDigits/@Range[1,(nn (nn+1)), 2]],Range[nn]]] (* Requires Mathematica version 11 or later *) (* Harvey P. Dale, Sep 23 2019 *)
Extensions
More terms from Hans Havermann, Sep 23 2002