A051369 a(n+1) = a(n) + sum of digits of a(n)^2, with a(1) = 3.

3, 12, 21, 30, 39, 48, 57, 75, 93, 120, 129, 147, 165, 183, 210, 219, 246, 264, 300, 309, 336, 363, 390, 399, 417, 453, 471, 489, 507, 534, 561, 579, 597, 624, 660, 678, 714, 750, 768, 804, 831, 858, 885, 912, 939, 966, 993, 1029, 1056, 1074, 1101, 1110, 1119

Offset: 1

Author

Miklos SZABO (mike(AT)ludens.elte.hu)

Keywords

• nonn
• base
• easy
• less

Links

• Paolo Xausa, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A033298.

Programs

Mathematica

NestList[# + DigitSum[#^2] &, 3, 100] (* Paolo Xausa, Mar 20 2025 *)