A083536 - OEIS

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A083536

First differences of noncototients A005278.

16, 8, 16, 2, 6, 28, 14, 16, 6, 8, 4, 12, 8, 16, 2, 14, 16, 4, 12, 4, 10, 12, 16, 6, 2, 6, 16, 2, 6, 12, 16, 14, 4, 2, 16, 4, 6, 14, 8, 10, 8, 24, 30, 4, 4, 8, 8, 28, 2, 12, 2, 2, 10, 8, 8, 4, 14, 4, 12, 30, 8, 16, 2, 14, 14, 6, 2, 10, 8, 16, 2, 6, 2, 14, 26, 6, 8, 8, 14, 10, 16, 8, 8, 22, 2, 28

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,1

LINKS

Amiram Eldar, Table of n, a(n) for n = 1..10000

FORMULA

a(n) = A005278(n+1) - A005278(n).

EXAMPLE

Missing terms from A051953 are 10,26,34,50,.. so their difference sequence starts with 16,8,16,...

MATHEMATICA

t0[x_] := Table[j, {j, 1, x}] t=Table[w-EulerPhi[w], {w, 1, 10000}]; u=Union[%]; Delete[u-RotateRight[u], 1]; c=Complement[t0[10000], u]; Delete[c-RotateRight[c], 1];

CROSSREFS

Cf. A051953, A005278.

Sequence in context: A102272 A304227 A305037 * A305583 A316690 A258160

Adjacent sequences: A083533 A083534 A083535 * A083537 A083538 A083539

KEYWORD

nonn

AUTHOR

Labos Elemer, May 20 2003

EXTENSIONS

a(84)-a(85) corrected by David Ng, (an error that was noticed by Doug Phillips), Oct 31 2016

a(86) corrected and name simplified by Omar E. Pol, Nov 04 2016

STATUS

approved