A165492 Primes p where the digital sum of p^2 is equal to 13.

7, 29, 47, 61, 79, 151, 349, 389, 461, 601, 1051, 1249, 1429, 1451, 1789, 2239, 3499, 4799, 5011, 5101, 5501, 5749, 10501, 11149, 14249, 50101, 51001, 55001, 100501, 100649, 101149, 150001, 318751, 448999, 501001, 1009951, 5000011, 5000101, 5001001, 50000101

Offset: 1

Author

Vincenzo Librandi, Sep 21 2009

Keywords

• nonn
• base

Examples

			29 is in the sequence because 29^2 = 841 and 8+4+1 = 13.
1789 is in the sequence because 1789^2 = 3200521 and 3+2+0+0+5+2+1 = 13.
		

Links

• Vincenzo Librandi and Hiroaki Yamanouchi, Table of n, a(n) for n = 1..61 (terms a(1)-a(44) from Vincenzo Librandi)

Crossrefs

Cf. A165502 - A165504.

Programs

Magma

[p: p in PrimesUpTo(5*10^7) | &+Intseq(p^2) eq 13]; // Vincenzo Librandi, Sep 26 2015

Mathematica

Select[Prime[Range[80000]],Total[IntegerDigits[#^2]]==13&]  (* Harvey P. Dale, Apr 08 2011 *)

Formula

{A000040(i) : A123157(i) = 13}. [R. J. Mathar, Sep 29 2009]

Extensions

More terms from R. J. Mathar, Sep 29 2009

a(37)-a(40) from Hiroaki Yamanouchi, Sep 23 2014