A063456 Integers of the form (9^k + 7^k + 5^k + 3^k) / k.

24, 82, 408, 2417, 47749656, 2156128030221919129327512, 90949221094977345106333896591433489609596374424, 2427494453818597812327163045156169047951843189933572121989273548733125452824

Offset

1,1

Comments

a(14) has 2084 digits. - Michael S. Branicky, Apr 27 2023

Links

Michael S. Branicky, Table of n, a(n) for n = 1..13

Prog

(PARI) j=[]; for(n=1, 210, a=9^n+7^n+5^n+3^n; if(Mod(a, n)==0, j=concat(j, (a/n)))); j
(Python)
def okexp(n): return (pow(9, n, n) + pow(7, n, n) + pow(5, n, n) + pow(3, n, n))%n == 0
print([(9**n + 7**n + 5**n + 3**n)//n for n in range(1, 100) if okexp(n)]) # Michael S. Branicky, Apr 27 2023

Crossrefs

Sequence in context: A318988 A182915 A030622 * A265646 A304158 A045946

Adjacent sequences: A063453 A063454 A063455 * A063457 A063458 A063459

Keyword

nonn

Author

Jason Earls, Jul 25 2001

Status

approved