A061090 Squares the sum of the squares of whose digits are squares.

1, 4, 9, 100, 400, 676, 841, 900, 1444, 4225, 10000, 24025, 40000, 42025, 42436, 43264, 66049, 67600, 84100, 90000, 109561, 119716, 144400, 155236, 239121, 244036, 248004, 252004, 335241, 355216, 362404, 373321, 422500, 643204, 664225

Offset: 1

Author

Amarnath Murthy, Apr 19 2001

Keywords

• nonn
• base

Comments

Contains 10^(2k) for all k.

More generally, if k is in this sequence so is 100k. - Charles R Greathouse IV, Sep 20 2012

Examples

			676 = 26^2, 6^2 + 7^2 + 6^2 = 121 = 11^2;
1444 = 38^2, 1^2 + 4^2 + 4^2 + 4^2 = 49 = 7^2.
		

References

• A. Murthy, Smarandache Pythagoras additive square sequence (to be published in Smarandache Notions Journal).

Links

• Charles R Greathouse IV, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A053057.

Programs

Maple

readlib(issqr): for n from 1 to 2000 do L1 := convert(n^2, base, 10): if issqr(sum(L1[i]^2, i=1..nops(L1))) then printf(`%d,`,n^2) fi: od:

Mathematica

Select[Range[1000]^2,IntegerQ[Sqrt[Total[IntegerDigits[#]^2]]]&] (* Harvey P. Dale, Apr 26 2025 *)

PARI

ssd(n)=n=digits(n);sum(i=1,#n,n[i]^2)
v=List();for(n=1,1e4,if(issquare(ssd(n^2)),listput(v,n^2))); Vec(v) \\ Charles R Greathouse IV, Sep 20 2012

Extensions

Corrected and extended by James Sellers, Apr 20 2001