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A221639
5^(5n+1) + 4^(5n+2) + 3^(5n).
1
22, 32252, 65664390, 169782108716, 494432831031942, 1508131365182857052, 4675059823042234224390, 14570804744329875486495116, 45494077913917911421604180742, 142128354195602915965174073201852, 444109492260384165827568467076384390
OFFSET
0,1
COMMENTS
All terms are multiples of 22.
REFERENCES
Hugo Steinhaus: Studentenfutter, Urania, Leipzig 1991, #5
FORMULA
G.f. -22*(1-2926*x+754280*x^2) / ( (243*x-1)*(3125*x-1)*(1024*x-1) ). - R. J. Mathar, Aug 09 2013
PROG
(Haskell)
a221639 n = 5 ^ (5 * n + 1) + 4 ^ (5 * n + 2) + 3 ^ (5 * n)
(PARI) a(n)=5^(5*n+1)+4^(5*n+2)+243^n \\ Charles R Greathouse IV, Aug 09 2013
CROSSREFS
Subsequence of A008593.
Sequence in context: A127486 A232847 A191946 * A078398 A280812 A060619
KEYWORD
nonn,easy
AUTHOR
Reinhard Zumkeller, Aug 08 2013
STATUS
approved