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A195116
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a(n) = (2+3^n)*(3+2^n).
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1
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12, 25, 77, 319, 1577, 8575, 48977, 286759, 1699817, 10137775, 60645377, 363332599, 2178384857, 13065493375, 78378545777, 470228096839, 2821239178697, 16927047127375, 101561119454177, 609363227843479, 3656168902513337, 21936982025631775
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OFFSET
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0,1
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LINKS
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FORMULA
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G.f.: (12-119*x+341*x^2-294*x^3)/((1-x)*(1-2*x)*(1-3*x)*(1-6*x)).
Sum_{i=0..n} a(i) = (1/10)*(12*6^n+45*3^n+40*2^n+60*n+23).
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MATHEMATICA
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PROG
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(Magma) [(2+3^n)*(3+2^n): n in [0..21]];
(PARI) for(n=0, 21, print1((2+3^n)*(3+2^n)", "));
(Python)
def a(n): return (2+3**n)*(3+2**n)
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CROSSREFS
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Cf. A060013 ((1+2^n)*(2+1) with n>3).
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KEYWORD
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nonn,easy
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AUTHOR
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STATUS
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approved
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