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A246422
Numbers in which cubes may end (in base 10).
3
0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 11, 12, 13, 16, 17, 19, 21, 23, 24, 25, 27, 28, 29, 31, 32, 33, 36, 37, 39, 41, 43, 44, 47, 48, 49, 51, 52, 53, 56, 57, 59, 61, 63, 64, 67, 68, 69, 71, 72, 73, 75, 76, 77, 79, 81, 83, 84, 87, 88, 89, 91, 92, 93, 96, 97, 99, 101, 103, 104, 107, 109, 111, 112, 113, 117
OFFSET
1,3
LINKS
EXAMPLE
33 is a member because 77^3 = 456533 is a cube ending in 33.
MATHEMATICA
Union@Flatten@Table[Mod[i^3, 10^n], {n, 3}, {i, 10^n}] (* Ivan Neretin, Aug 30 2015*)
PROG
(PARI)
v=[]; for(k=1, 10^3, for(m=1, 3, v=concat(v, k^3%10^m))); v=vecsort(v, , 8)
(PARI)
a=[]; for(m=1, 3, a=setunion(a, Set(vector(10^m, n, n^3)%10^m))); a
(Python)
from itertools import count, islice
from sympy import nthroot_mod
def A246422_gen(startvalue=0): # generator of terms >= startvalue
return filter(lambda n:len(nthroot_mod(n, 3, 10**(len(str(n))))), count(max(startvalue, 0)))
A246422_list = list(islice(A246422_gen(), 20)) # Chai Wah Wu, Feb 16 2023
CROSSREFS
Sequence in context: A081061 A317589 A141807 * A072495 A257671 A285523
KEYWORD
nonn,base,changed
AUTHOR
Derek Orr, Aug 25 2014
EXTENSIONS
Corrected by Ivan Neretin, Mar 03 2016
STATUS
approved