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A078865 Difference of consecutive primorial numbers divided by 4. 0
1, 6, 45, 525, 6930, 120120, 2297295, 53348295, 1561650090, 48522699225, 1805044411170, 74207381348100, 3194627767035705, 150451755314205345, 7993567173650388330, 472542797919255648585, 28841405252313189586050 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..17.

EXAMPLE

n=3:(210-30)/4=45=a[3]

MATHEMATICA

q[x_] := Apply[Times, Table[Prime[j], {j, 1, x}]] Table[(q[w+1]-q[w])/4, {w, 1, 20}]

CROSSREFS

Cf. A002110, A016825.

Sequence in context: A294642 A109516 A245493 * A160492 A318017 A273091

Adjacent sequences:  A078862 A078863 A078864 * A078866 A078867 A078868

KEYWORD

easy,nonn

AUTHOR

Labos Elemer, Dec 16 2002

STATUS

approved

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Last modified December 13 20:06 EST 2018. Contains 318087 sequences. (Running on oeis4.)