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A082076 First differences of primes of the form 4k+3 (A002145), divided by 4. 5
1, 1, 2, 1, 2, 3, 1, 3, 2, 1, 2, 1, 5, 1, 5, 1, 2, 3, 3, 1, 3, 3, 2, 3, 3, 1, 3, 3, 3, 2, 3, 6, 1, 5, 4, 3, 2, 3, 1, 9, 3, 2, 1, 5, 1, 3, 2, 1, 2, 1, 5, 6, 4, 2, 4, 3, 2, 3, 3, 3, 1, 3, 6, 2, 7, 2, 3, 1, 2, 9, 6, 3, 1, 3, 5, 1, 5, 1, 5, 1, 2, 7, 5, 1, 3, 2, 7, 3, 2, 3, 3, 6, 1, 3, 5, 7, 3, 2, 4, 9, 2, 7, 5, 1, 2 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

Table of n, a(n) for n=1..105.

FORMULA

a(n)=[A002145(n+1)-A002145(n)]/4

EXAMPLE

First and second 4k+3 primes are 3 and 7, so a(1)=(7-3)/4=1.

MATHEMATICA

k=0; m=4; r=3; Do[s=Mod[Prime[n], m]; If[Equal[s, r], rp=ep; k=k+1; ep=Prime[n]; Print[(ep-rp)/4]; ], {n, 1, 1000}]

CROSSREFS

Cf. A002144, A002145, A082073-A082075.

Sequence in context: A214261 A097825 A002343 * A231516 A048793 A249783

Adjacent sequences:  A082073 A082074 A082075 * A082077 A082078 A082079

KEYWORD

nonn

AUTHOR

Labos Elemer, Apr 07 2003

STATUS

approved

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Last modified October 22 18:08 EDT 2019. Contains 328319 sequences. (Running on oeis4.)