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.

A225049 Numbers that can be expressed as n plus sum of squared digits(n) in more than one way.

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%I A225049 #17 Apr 27 2013 15:00:00
%S A225049 30,41,56,81,95,96,98,101,112,114,121,125,131,142,146,152,157,168,173,
%T A225049 177,182,186,191,196,197,199,206,209,213,215,216,217,227,230,232,234,
%U A225049 240,243,245,247,248,257,260,262,266,272,276,284,285,287,292,299,300
%N A225049 Numbers that can be expressed as n plus sum of squared digits(n) in more than one way.
%H A225049 Christian N. K. Anderson, <a href="/A225049/b225049.txt">Table of n, a(n) for n = 1..10000</a>
%H A225049 Christian N. K. Anderson, <a href="/A225049/a225049.txt">All the integers that yield a(n)</a> for n=1..10000
%e A225049 a(13) = 131 is included because 131 = 57+5^2+7^2 = 73+7^2+3^2 = 105+1^2+5^2 = 122 + 1^2+4^2+4^2.
%o A225049 (R) digsqsum<-function(x) sum(as.numeric(unlist(strsplit(as.character(x),split="")))^2)
%o A225049 1:500+sapply(1:500,digsqsum)->y
%o A225049 table(y)->ty; names(ty[ty>1])
%Y A225049 Cf. A225048, A003052, A003219, A003132, A062028, A066568.
%K A225049 nonn,base
%O A225049 1,1
%A A225049 _Kevin L. Schwartz_ and _Christian N. K. Anderson_, Apr 25 2013