A029783
Exclusionary squares: numbers n such that no digit of n is present in n^2.
Original entry on oeis.org
2, 3, 4, 7, 8, 9, 17, 18, 22, 24, 29, 33, 34, 38, 39, 44, 47, 53, 54, 57, 58, 59, 62, 67, 72, 77, 79, 84, 88, 92, 94, 144, 157, 158, 173, 187, 188, 192, 194, 209, 212, 224, 237, 238, 244, 247, 253, 257, 259, 307, 313, 314, 333, 334, 338, 349, 353, 359
Offset: 1
From _M. F. Hasler_, Oct 16 2018: (Start)
It is easy to construct infinite subsequences of the form S(a,b)(n) = a*R(n) + b, where R(n) = (10^n-1)/9 is the repunit of length n. Among these are:
S(3,0) = (3, 33, 333, ...), S(3,1) = (4, 34, 334, 3334, ...), S(3,5) = (8, 38, 338, ...), also b = 26, 44, 434, ... (with a = 3); S(6,1) = (7, 67, 667, ...), S(6,6) = (72, 672, 6672, ...) (excluding n=1), S(6,7) = (673, 6673, ...) (excluding also n=2 here), S(6,-7) = (59, 659, 6659, ...), and others. (End)
- Clifford A. Pickover, A Passion for Mathematics, Wiley, 2005; see p. 60.
- David Wells, The Penguin Dictionary of Curious and Interesting Numbers, Revised Edition, 1997, page 144, entry 567.
Cf.
A059930 (n and n^2 use different digits),
A112736 (numbers whose squares are exclusionary).
-
a029783 n = a029783_list !! (n-1)
a029783_list = filter (\x -> a258682 x == x ^ 2) [1..]
-- Reinhard Zumkeller, Jun 07 2015, Apr 16 2011
-
Select[Range[1000], Intersection[IntegerDigits[ # ], IntegerDigits[ #^2]] == {} &] (* Tanya Khovanova, Dec 25 2006 *)
-
is_A029783(n)=!#setintersect(Set(digits(n)),Set(digits(n^2))) \\ M. F. Hasler, Oct 16 2018
-
# see linked program
-
from itertools import count, islice
def A029783_gen(startvalue=0): # generator of terms >= startvalue
return filter(lambda n:not set(str(n))&set(str(n**2)),count(max(startvalue,0)))
A029783_list = list(islice(A029783_gen(),30)) # Chai Wah Wu, Feb 12 2023
A111116
Numbers n such that digits of n are not present in n^4.
Original entry on oeis.org
2, 3, 4, 7, 8, 9, 24, 27, 28, 32, 33, 42, 52, 53, 58, 59, 67, 77, 88, 89, 93, 202, 203, 258, 284, 303, 324, 329, 377, 383, 422, 669, 818, 832, 843, 878, 882, 887, 949, 2027, 2042, 2673, 3144, 3222, 3253, 3302, 3308, 3737, 3773, 3953, 3979, 3983, 4779, 5353, 5669
Offset: 1
For the corresponding n^4, see
A113316.
-
Select[Range[6000], Intersection[IntegerDigits[ # ], IntegerDigits[ #^4]] == {} &] (* Ray Chandler, Oct 17 2005 *)
fQ[n_] := Intersection[ Union[ IntegerDigits[n]], Union[ IntegerDigits[n^4]]] == {}; Select[ Range[ 5887], fQ[ # ] &] (* Robert G. Wilson v *)
-
A111116_list = [n for n in range(1,10**6) if set(str(n)) & set(str(n**4)) == set()]
# Chai Wah Wu, Jan 05 2015
A113316
Fourth powers m^4 none of whose digits are present in their corresponding roots m.
Original entry on oeis.org
16, 81, 256, 2401, 4096, 6561, 331776, 531441, 614656, 1048576, 1185921, 3111696, 7311616, 7890481, 11316496, 12117361, 20151121, 35153041, 59969536, 62742241, 74805201, 1664966416, 1698181681, 4430766096, 6505390336, 8428892481
Offset: 1
-
Select[Range[350]^4,Intersection[IntegerDigits[#], IntegerDigits[ Surd[ #,4]]] =={}&] (* Harvey P. Dale, Dec 19 2015 *)
A029784
Squares such that digits of sqrt(n) are not present in n.
Original entry on oeis.org
4, 9, 16, 49, 64, 81, 289, 324, 484, 576, 841, 1089, 1156, 1444, 1521, 1936, 2209, 2809, 2916, 3249, 3364, 3481, 3844, 4489, 5184, 5929, 6241, 7056, 7744, 8464, 8836, 20736, 24649, 24964, 29929, 34969, 35344, 36864, 37636, 43681, 44944, 50176, 56169, 56644
Offset: 1
-
Select[Range[500], {} == Intersection @@ IntegerDigits[{#, #^2}] &]^2 (* Giovanni Resta, Aug 08 2018 *)
A029786
Cubes such that digits of cube root of n are not present in n.
Original entry on oeis.org
8, 27, 343, 512, 10648, 19683, 79507, 103823, 110592, 140608, 148877, 250047, 314432, 456533, 778688, 3869893, 5088448, 5545233, 6539203, 6644672, 7077888, 10941048, 11089567, 16003008, 18191447, 27818127, 54010152, 67917312, 75686967, 86350888, 96071912
Offset: 1
-
Select[Range[1000], {} == Intersection @@ IntegerDigits[{#, #^3}] &]^3 (* Giovanni Resta, Aug 08 2018 *)
A030087
Primes such that digits of p do not appear in p^3.
Original entry on oeis.org
2, 3, 7, 43, 47, 53, 157, 223, 263, 487, 577, 587, 823, 4657, 5657, 6653, 7177, 8287, 9343, 26777, 36293, 46477, 58787, 72727, 75707, 176777, 363313, 530353, 566653, 959953, 1771787, 2525557, 2555353, 2626277, 3656363, 4414447, 7110707, 8448343, 20700077, 54475457, 71117177, 72722977, 135135113, 393321293, 457887457, 505053053, 672722627
Offset: 1
2 and 2^3=8 have no digits in common, hence 2 is in the sequence.
Cf.
A029785 (digits of n are not present in n^3),
A030086 (similar, with p^2),
A253574 (similar, with p^4).
-
Select[Prime[Range[1500000]], Intersection[IntegerDigits[#], IntegerDigits[#^3]]=={} &] (* Vincenzo Librandi, Jan 04 2015 *)
-
lista(nn) = {forprime (n=1, nn, if (#setintersect(Set(vecsort(digits(n^3))), Set(vecsort(digits(n)))) == 0, print1(n, ", ")); ); } \\ Michel Marcus, Jan 04 2015
-
from sympy import isprime
A030087_list = [n for n in range(1,10**6) if set(str(n)) & set(str(n**3)) == set() and isprime(n)]
# Chai Wah Wu, Jan 05 2015
A112994
Numbers whose cubes are exclusionary: numbers k such that k has no repeated digits and k and k^3 have no digits in common.
Original entry on oeis.org
2, 3, 7, 8, 27, 43, 47, 48, 52, 53, 63, 68, 92, 157, 172, 187, 192, 263, 378, 408, 423, 458, 468, 478, 487, 527, 587, 608, 648, 692, 823, 843, 918, 1457, 1587, 1592, 4657, 4732, 5692, 6058, 6378, 7658
Offset: 1
- H. Ibstedt, Solution to Problem 2623, "Exclusionary Powers", pp. 346-9, Journal of Recreational Mathematics, vol. 32 No.4 2003-4, Baywood NY.
- Clifford A. Pickover, A Passion for Mathematics, Wiley, 2005; see p. 60.
The corresponding cubes are in
A112993.
-
Select[Range[8000],Max[DigitCount[#]]==1&&Intersection[IntegerDigits[ #],IntegerDigits[#^3]]=={}&] (* Harvey P. Dale, Sep 06 2021 *)
-
isok(n) = my(digs = digits(n)); (#digs == #Set(digs)) && (#setintersect(Set(digs), Set(digits(n^3))) == 0); \\ Michel Marcus, Oct 26 2013
-
def ok(n):
s = str(n)
return len(s) == len(set(s)) and set(s) & set(str(n**3)) == set()
print([k for k in range(7659) if ok(k)]) # Michael S. Branicky, Aug 27 2021
-
# version for verifying full sequence
from itertools import permutations
def no_repeated_digits():
for d in range(1, 11):
for p in permutations("0123456789", d):
if p[0] == '0': continue
yield int("".join(p))
def afull():
alst = []
for k in no_repeated_digits():
if set(str(k)) & set(str(k**3)) == set():
alst.append(k)
return alst
print(afull()) # Michael S. Branicky, Aug 27 2021
A247883
Consecutive exclusionary cubes: Digits of n are not present in n^3 and digits of n+1 are not present in (n+1)^3.
Original entry on oeis.org
2, 7, 47, 52, 187, 222, 477, 587, 5522, 6777
Offset: 1
-
filter:= proc(n) convert(convert(n,base,10),set) intersect convert(convert(n^3,base,10),set) = {} end proc:
select(t -> filter(t) and filter(t+1), [seq(i,i=2..10^6, 5)]); # Robert Israel, Mar 10 2025
-
for(n=1,10^6,s=digits(n);t=digits(n+1);s3=digits(n^3);t3=digits((n+1)^3);if(#vecsort(concat(s,s3),,8)==#vecsort(s,,8)+#vecsort(s3,,8)&vecsort(concat(t,t3),,8)==#vecsort(t,,8)+#vecsort(t3,,8),print1(n,", ")))
-
for n in range(10**6):
s, t = str(n), str(n+1)
s3, t3 = str(n**3), str((n+1)**3)
c = 0
for i in s:
if s3.count(i):
c += 1
break
for j in t:
if t3.count(j):
c += 1
break
if not c:
print(n, end=', ')
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