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A250222 a(n) = phi(2n+1) - phi(2n), where phi is A000010. 0
1, 2, 4, 2, 6, 8, 2, 8, 12, 4, 12, 12, 6, 16, 22, 4, 8, 24, 6, 24, 30, 4, 24, 26, 12, 28, 22, 12, 30, 44, 6, 16, 46, 12, 46, 48, 4, 24, 54, 22, 42, 40, 14, 48, 48, 16, 26, 64, 18, 60, 70, 0, 54, 72, 32, 64, 52, 16, 38, 78, 20, 40, 90, 20, 82, 68, 6, 72, 94, 44, 50, 64 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

a(157) = -12 is the first negative number in this sequence.

LINKS

Table of n, a(n) for n=1..72.

CROSSREFS

Cf. A000010, A057000.

Sequence in context: A216369 A083791 A303347 * A026251 A205721 A085190

Adjacent sequences:  A250219 A250220 A250221 * A250223 A250224 A250225

KEYWORD

nonn

AUTHOR

Eric Chen, Dec 24 2014

STATUS

approved

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Last modified April 23 03:26 EDT 2019. Contains 322380 sequences. (Running on oeis4.)