cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A082927 Numbers in which at least one pair of adjacent digits differ by 1.

This page as a plain text file.
%I A082927 #21 Oct 29 2022 06:02:16
%S A082927 10,12,21,23,32,34,43,45,54,56,65,67,76,78,87,89,98,100,101,102,103,
%T A082927 104,105,106,107,108,109,110,112,120,121,122,123,124,125,126,127,128,
%U A082927 129,132,134,143,145,154,156,165,167,176,178,187,189,198,201,210,211,212,213
%N A082927 Numbers in which at least one pair of adjacent digits differ by 1.
%F A082927 a(n) = n + O(x^0.915), where the exponent is the log(k)/log(10) with k the largest root of x^5 - 9x^4 + 4x^3 + 21x^2 - 9x - 5. - _Charles R Greathouse IV_, Mar 11 2014
%e A082927 1998 is a term because 8 and 9 differ by 1.
%t A082927 Select[Range[250],MemberQ[Abs[Differences[IntegerDigits[#]]],1]&] (* _Harvey P. Dale_, Apr 07 2018 *)
%o A082927 (PARI) isok(n) = (d = digits(n)) && (sum(i=1, #d-1, abs(d[i] - d[i+1])==1) >= 1); \\ _Michel Marcus_, Mar 11 2014
%K A082927 base,easy,nonn
%O A082927 1,1
%A A082927 Anonymous, Apr 15 2003
%E A082927 120 added by _Zak Seidov_, Mar 11 2014
%E A082927 Name clarified by _Jon E. Schoenfield_, Oct 29 2022