A135554 Numbers k such that k is the fourth power of an integer and the sum of digits of k is prime.

16, 256, 625, 2401, 4096, 83521, 160000, 279841, 456976, 1048576, 1500625, 2560000, 2825761, 3748096, 4477456, 4879681, 5764801, 6250000, 7890481, 9834496, 11316496, 14776336, 16777216, 20151121, 21381376, 24010000, 28398241, 33362176, 40960000, 54700816

Offset: 1

Author

Enoch Haga, Nov 25 2007

Keywords

• easy
• nonn
• base
• changed

Comments

Intersection of A000583 and A028834. - Michel Marcus, Oct 19 2016

Examples

			a(1)=16 because 2^4=16 and 1+6=7, prime.
		

Links

• G. C. Greubel, Table of n, a(n) for n = 1..1090

Crossrefs

Cf. A000583, A028834, A135555.

Programs

Mathematica

Select[Range[90]^4,PrimeQ[Total[IntegerDigits[#]]]&] (* Harvey P. Dale, Dec 13 2010 *)

PARI

isok(n) = ispower(n,4) && isprime(sumdigits(n)); \\ Michel Marcus, Oct 19 2016

Extensions

Description corrected by Harvey P. Dale, Dec 13 2010