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.

A061424 Sum of digits = 7 times number of digits.

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%I A061424 #14 Oct 22 2022 16:54:22
%S A061424 7,59,68,77,86,95,399,489,498,579,588,597,669,678,687,696,759,768,777,
%T A061424 786,795,849,858,867,876,885,894,939,948,957,966,975,984,993,1999,
%U A061424 2899,2989,2998,3799,3889,3898,3979,3988,3997,4699,4789,4798,4879,4888,4897
%N A061424 Sum of digits = 7 times number of digits.
%H A061424 Robert Israel, <a href="/A061424/b061424.txt">Table of n, a(n) for n = 1..10000</a>
%e A061424 498 is a term as the arithmetic mean of the digits is (4+9+8)/3 = 7.
%p A061424 filter:= proc(n) local L;
%p A061424   L:= convert(n,base,10);
%p A061424   convert(L,`+`)=nops(L)*7
%p A061424 end proc:
%p A061424 select(filter, [$1..10000]); # _Robert Israel_, Dec 07 2020
%t A061424 Select[Range[5000],Total[IntegerDigits[#]]==7IntegerLength[#]&] (* _Harvey P. Dale_, Oct 22 2022 *)
%Y A061424 Cf. A061383-A061388, A061423-A061425.
%K A061424 nonn,base,easy
%O A061424 1,1
%A A061424 _Amarnath Murthy_, May 03 2001
%E A061424 More terms from Larry Reeves (larryr(AT)acm.org), May 16 2001
%E A061424 Offset changed by _Robert Israel_, Dec 07 2020