A048394 -id:A048394 - cp's OEIS frontend

A048390 Digits d in decimal expansion of n replaced with d^3.

0, 1, 8, 27, 64, 125, 216, 343, 512, 729, 10, 11, 18, 127, 164, 1125, 1216, 1343, 1512, 1729, 80, 81, 88, 827, 864, 8125, 8216, 8343, 8512, 8729, 270, 271, 278, 2727, 2764, 27125, 27216, 27343, 27512, 27729, 640, 641, 648, 6427, 6464, 64125, 64216, 64343

Offset: 0

Patrick De Geest, Mar 15 1999

Vincenzo Librandi, Table of n, a(n) for n = 0..1000

Cf. A048391, A048392, A048393, A048394.

[0] cat [StringToInteger(&cat[IntegerToString(h): h in Reverse([i^3: i in Intseq(n)])]): n in [1..50]]; // Vincenzo Librandi, Mar 12 2013

FromDigits[Flatten[IntegerDigits/@(IntegerDigits[#]^3)]]&/@ Range[0,50] (* Harvey P. Dale, Jun 04 2011 *)

a(n) = my(d = digits(n)); my(s = ""); for (k=1, #d, s = concat(s, Str(d[k]^3))); eval(s); \\ Michel Marcus, Nov 06 2016

A048393 Replacing digits d in decimal expansion of n with d^3 yields a prime.

Original entry on oeis.org

11, 13, 23, 31, 41, 43, 53, 61, 73, 101, 107, 109, 121, 137, 143, 149, 151, 157, 161, 169, 173, 181, 191, 211, 217, 221, 229, 233, 241, 253, 257, 259, 271, 277, 281, 299, 307, 311, 313, 319, 323, 331, 421, 427, 431, 449, 469, 493, 511, 527, 541, 577, 589

Offset: 1

Patrick De Geest, Mar 15 1999

			313 = (3)(1)(3) -> (27)(1)(27) = 27127, which is a prime.

Cf. A048390, A048394.

Select[Range[600],PrimeQ[FromDigits[Flatten[IntegerDigits/@ (IntegerDigits[ #]^3)]]]&] (* Harvey P. Dale, Jan 27 2015 *)

from sympy import primerange, isprime
for n in primerange(2,600):
    t=int(''.join(str(int(i)**3) for i in str(n)))
    if sympy.isprime(t):
         print(n)
# Abhiram R Devesh, Feb 09 2015

Offset corrected by Michel Marcus, Oct 19 2016

cp's OEIS Frontend

A048390 Digits d in decimal expansion of n replaced with d^3.

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