A229058 Primes p where the digital sum of p^2 is equal to 25.

67, 113, 157, 193, 257, 283, 311, 337, 373, 409, 419, 463, 509, 599, 643, 653, 661, 743, 761, 769, 797, 1013, 1031, 1039, 1103, 1129, 1193, 1237, 1301, 1381, 1399, 1427, 1471, 1481, 1553, 1571, 1579, 1597, 1733, 1759, 1823, 1831, 1877, 2029, 2039, 2111, 2129

Offset: 1

Author

Vincenzo Librandi, Sep 12 2013

Keywords

• nonn

Comments

From Bruno Berselli, Sep 12 2013: (Start)

Primes q such that the digital sum of q^2 is 1 < k < 50:

k | q

---|------------

4 | 2, 11, 101;

7 | A226803;

9 | 3;

10 | A226802;

13 | A165492;

16 | A165459;

19 | A165493;

22 | 43, 97, 191, 227, 241, 317, 331, 353, ... ;

25 | this sequence;

28 | 163, 197, 233, 307, 359, 397, 431, 467, ... ;

31 | A165502;

34 | 167, 293, 383, 563, 607, 617, 733, 787, ... ;

37 | A165504;

40 | 313, 947, 983, 1303, 1483, 1609, 1663, ... ;

43 | A165504;

46 | 883, 937, 1367, 1637, 2213, 2447, 2683, ... ;

49 | 1667, 2383, 2437, 2617, 2963, 4219, 4457, ... . (End)

Links

• Vincenzo Librandi, Table of n, a(n) for n = 1..1000

Crossrefs

Cf. A165459, A165492, A165493, A165502-A165504, A226802, A226803.

Programs

Magma

[p: p in PrimesUpTo(2600) | &+Intseq(p^2) eq 25];

Mathematica

Select[Prime[Range[400]], Total[IntegerDigits[#^2]] == 25 &]