A226803 Primes p where the digital sum of p^2 is equal to 7.

5, 149, 1049

Offset: 1

Author

Vincenzo Librandi, Jun 24 2013

Keywords

• nonn
• base
• bref
• more

Comments

No more terms below 10^9. - Michel Marcus, Nov 02 2013

No more terms below 10^20. - Hiroaki Yamanouchi, Sep 23 2014

Examples

			5 is in the sequence because 5^2 = 25 and 2 + 5 = 7.
149 is in the sequence because 149^2 = 22201 and 2 + 2 + 2 + 0 + 1 = 7.
		

Crossrefs

Subsequence of A215614.

Cf. A226802, A165492, A165459, A165493.

Programs

Magma

[p: p in PrimesUpTo(6*10^6) | &+Intseq(p^2) eq 7];

Mathematica

Select[Prime[Range[10000]], Total[IntegerDigits[#^2]] == 7 &]

PARI

lista(nn) = {forprime(p=2, nn, if (sumdigits(p^2)==7, print1(p, ", ")););} \\ Michel Marcus, Nov 02 2013

Extensions

Keywords fini,full, since unproven, removed by Max Alekseyev, Jun 20 2025