[go: up one dir, main page]

login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

Search: a136292 -id:a136292
     Sort: relevance | references | number | modified | created      Format: long | short | data
Primes of the form a^a + b^b + c^c + d^d + e^e + f^f.
+10
1
41, 47, 61, 67, 113, 139, 293, 313, 571, 797, 823, 1307, 3191, 3391, 3463, 3643, 3947, 4153, 6257, 6263, 6793, 7019, 9433, 12757, 15629, 15881, 46687, 46919, 46997, 47681, 49811, 49843, 50069, 50321, 53419, 56039, 56543, 59183, 93319
OFFSET
1,1
LINKS
FORMULA
A000040 INTERSECTION {A000312(a) + A000312(b) + A000312(c) + A000312(d) + A000312(e) + A000312(f)}.
EXAMPLE
a(1) = 41 = 1^1 + 1^1 + 2^2 + 2^2 + 2^2 + 3^3.
a(2) = 47 = 2^2 + 2^2 + 2^2 + 2^2 + 2^2 + 3^3.
a(3) = 61 = 1^1 + 1^1 + 1^1 + 2^2 + 3^3 + 3^3.
a(4) = 67 = 1^1 + 2^2 + 2^2 + 2^2 + 3^3 + 3^3.
a(5) = 113 = 1^1 + 2^2 + 3^3 + 3^3 + 3^3 + 3^3.
MATHEMATICA
Select[Union[ Flatten[Table[ a^a + b^b + c^c + d^d + e^e + f^f, {a, 1, 20}, {b, 1, a}, {c, 1, b}, {d, 1, c}, {e, 1, d}, {f, 1, e}]]], PrimeQ]
PROG
(PARI) v=[]; for(a=1, 30, for(b=1, a, for(c=1, b, for(d=1, c, for(e=1, d, for(f=1, e, if(ispseudoprime(t=a^a+b^b+c^c+d^d+e^e+f^f), v=concat(v, t)))))))); #v \\ Charles R Greathouse IV, Feb 15 2011
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Jonathan Vos Post, Apr 11 2008
STATUS
approved

Search completed in 0.005 seconds