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A369956
a(n) is the least integer m such that the sum of the digits of m^2 is k+n where k is the number of digits of n.
1
1, 101, 11, 2, 149, 32, 4, 12, 3, 8, 106, 16, 7, 103, 13, 108, 24, 17, 1019, 124, 43, 1013, 113, 67, 114, 63, 10024, 1024, 133, 83, 1067, 167, 1044, 264, 314, 10087, 1303, 313, 10093, 1183, 707, 1374, 1333, 836, 10343, 1667, 100264, 10714, 2236, 10386, 3114
OFFSET
0,2
LINKS
EXAMPLE
a(5)=32 because 32 is the least integer with 2 digits and 32^2=1024 and 1+0+2+4=2+5.
MATHEMATICA
Table[SelectFirst[Range@200000, Total[IntegerDigits[#^2]]==n+Length@IntegerDigits@#&], {n, 0, 50}]
CROSSREFS
KEYWORD
nonn,base,easy
AUTHOR
Zhining Yang, Feb 06 2024
STATUS
approved