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A063077 a(n) = phi(n^2 + 1) - 2n. 1
-1, 0, -2, 8, 2, 24, 6, 32, 22, 80, 38, 88, 38, 168, 82, 224, 78, 204, 142, 360, 150, 340, 162, 528, 262, 624, 234, 568, 362, 772, 370, 736, 366, 988, 542, 1224, 470, 1012, 682, 1520, 730, 1324, 634, 1688, 922, 1924, 674, 1744, 1102, 2300, 1198, 2056, 1014, 2808, 1298, 3024, 1086, 2572, 1622, 3192, 1738, 2948 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

Harry J. Smith, Table of n, a(n) for n = 1..1000

MAPLE

with(numtheory); A063077:=n->phi(n^2+1)-2*n; seq(A063077(k), k=1..100); # Wesley Ivan Hurt, Oct 24 2013

MATHEMATICA

Table[EulerPhi[n^2 + 1] - 2 n, {n, 100}] (* Wesley Ivan Hurt, Oct 24 2013 *)

PROG

(PARI) a(n)={eulerphi(n^2 + 1) - 2*n}

CROSSREFS

Sequence in context: A175183 A189217 A183037 * A245995 A085192 A320972

Adjacent sequences:  A063074 A063075 A063076 * A063078 A063079 A063080

KEYWORD

easy,sign

AUTHOR

Jason Earls, Aug 05 2001

STATUS

approved

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Last modified January 25 03:49 EST 2020. Contains 331241 sequences. (Running on oeis4.)