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A124899
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Sierpinski quotient ((2n-1)^(2n-1) + 1)/(2n) = A014566(2n-1)/(2n).
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4
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1, 7, 521, 102943, 38742049, 23775972551, 21633936185161, 27368368148803711, 45957792327018709121, 98920982783015679456199, 265572137199362841880960201, 870019499993663001431459704607, 3416070845000481662841943594125601
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OFFSET
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1,2
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COMMENTS
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2n divides Sierpinski number A014566(2n-1).
2^n divides A014566(2^n-1); A014566(2^n - 1) / 2^n = A081216(2^n - 1) = A122000(n) = {1, 7, 102943, 27368368148803711, 533411691585101123706582594658103586126397951, ...}.
p+1 divides A014566(p) for prime p; A014566(p)/(p+1) = A056852(n) = {7, 521, 102943, 23775972551, 21633936185161, ...}.
Primes in this sequence are {7, 521, 45957792327018709121}.
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LINKS
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FORMULA
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a(n) = ((2n-1)^(2n-1) + 1)/(2n) = A014566(2n-1)/(2n).
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MAPLE
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seq(((2*n-1)^(2*n-1)+1)/(2*n), n=1..20); # Muniru A Asiru, Apr 08 2018
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MATHEMATICA
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Table[((2n-1)^(2n-1)+1)/(2n), {n, 1, 20}]
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PROG
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(GAP) List([1..15], n->((2*n-1)^(2*n-1)+1)/(2*n)); # Muniru A Asiru, Apr 08 2018
(PARI) a(n) = ((2*n-1)^(2*n-1) + 1)/(2*n); \\ Michel Marcus, Apr 08 2018
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CROSSREFS
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Cf. A014566 (Sierpinski numbers of the first kind: n^n + 1).
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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