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A291625
Numbers k such that 0 is the smallest decimal digit of k^2.
6
10, 20, 30, 32, 33, 40, 45, 47, 48, 49, 50, 51, 52, 53, 55, 60, 64, 70, 71, 78, 80, 84, 90, 95, 97, 98, 99, 100, 101, 102, 103, 104, 105, 110, 120, 130, 138, 140, 142, 143, 144, 145, 147, 148, 149, 150, 151, 152, 153, 155, 160, 170, 174, 175, 176, 179, 180
OFFSET
1,1
EXAMPLE
47 is in the sequence because 47^2 = 2209, the smallest decimal digit of which is 0.
PROG
(PARI) select(k->vecmin(digits(k^2))==0, vector(1000, k, k))
(Python)
A291625_list = [k for k in range(1, 10**6) if '0' in str(k**2)] # Chai Wah Wu, Aug 28 2017
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Colin Barker, Aug 28 2017
STATUS
approved