A254958 -id:A254958 - cp's OEIS frontend

A290934 a(n) equals the sum of the squares of the digits of A254958(n).

1, 4, 9, 16, 25, 36, 49, 64, 81, 25, 25, 100, 100, 9, 81, 81, 9, 9, 49, 36, 49, 121, 121, 49, 49, 81, 81, 36, 36, 81, 81, 81, 144, 49, 121, 49, 81, 81, 121, 121, 121, 81, 121, 81, 81, 144, 144, 121, 121, 4, 36, 36, 100, 25, 25, 36, 100, 36, 100, 25, 49, 36, 36

Offset: 1

Jonathan Schwartz, Aug 14 2017

Jonathan Schwartz, Table of n, a(n) for n = 1..1000

Cf. A000290, A003132, A254958.

import java.util.ArrayList;public class Seq {public static void main(String[] args) {int l = 1000;
ArrayList squares = new ArrayList();
for (int i = 1; i <= l; i++) {squares.add((i * i));}
int term = 1;
for (int n = 1; n < Integer.MAX_VALUE; n++) {
if (!(Integer.toString(n).contains("0")))
if (squares.contains(sum(n))){
int k = 0;
for(int i = 0;i1000)break;}}
static int sum(int n) {int s = 0;String str = Integer.toString(n);for (int i = 0; i < str.length(); i++) {s += (Integer.valueOf(Character.toString(str.charAt(i)))*Integer.valueOf(Character.toString(str.charAt(i))));}return s;}}

Select[Map[Total, Select[Array[IntegerDigits, 1550], FreeQ[#, 0] &]^2], IntegerQ@ Sqrt@ # &] (* Michael De Vlieger, Aug 15 2017 *)

lista(nn) = {for (n=1, nn, d = digits(n); if (vecmin(d) && issquare(s=sum(k=1, #d, d[k]^2)), print1(s, ", ")););} \\ Michel Marcus, Aug 28 2017

A254959 Squares not divisible by 10 with digits d_1, d_2, ... d_k such that d_1^2 + ... + d_k^2 is a square.

Original entry on oeis.org

1, 4, 9, 676, 841, 1444, 4225, 24025, 42025, 42436, 43264, 66049, 109561, 119716, 155236, 239121, 244036, 248004, 252004, 335241, 355216, 362404, 373321, 643204, 664225, 703921, 717409, 751689, 790321, 802816, 840889, 850084, 851929, 1110916, 1263376, 1292769, 1334025, 1361889, 1366561, 1371241, 1413721, 1522756, 1718721

Offset: 1

Derek Orr, Feb 11 2015

Any one of these terms can have an even number of 0's following the term. Thus, the numbers ending in 0 have been omitted.

Harvey P. Dale, Table of n, a(n) for n = 1..1000

Cf. A000290, A254958.

Select[Range[1500]^2,Mod[#,10]!=0&&IntegerQ[Sqrt[Total[ IntegerDigits[ #]^2]]]&] (* Harvey P. Dale, Apr 29 2019 *)

for(n=0,10^3,if(n%10,N=n^2;d=digits(N);s=0;for(i=1,#d,s+=d[i]^2);if(issquare(s),print1(N,", "))))

cp's OEIS Frontend

A290934 a(n) equals the sum of the squares of the digits of A254958(n).

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