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 A082073 First difference set of primes with 4k+1 form: A002144. 10
 8, 4, 12, 8, 4, 12, 8, 12, 16, 8, 4, 8, 4, 24, 12, 8, 16, 8, 12, 4, 32, 4, 8, 16, 12, 8, 4, 12, 20, 4, 20, 12, 4, 20, 16, 8, 4, 8, 12, 12, 16, 8, 4, 48, 12, 20, 16, 12, 8, 16, 8, 12, 4, 24, 12, 8, 12, 4, 24, 8, 24, 24, 4, 8, 4, 24, 12, 12, 8, 24, 4, 20, 4, 48, 8, 4, 12, 24, 20, 12, 4, 8, 12 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS a(n) is divisible by 4, for all n. LINKS Charles R Greathouse IV, Table of n, a(n) for n = 1..10000 FORMULA a(n) = A002144(n+1) - A002144(n). EXAMPLE first and second 4k+1 primes are 5 and 13, so a(1)=13-5=8; MATHEMATICA k=0; m=4; r=1; Do[s=Mod[Prime[n], m]; If[Equal[s, r], rp=ep; k=k+1; ep=Prime[n]; Print[(ep-rp)]; ], {n, 1, 1000}] Differences[Select[Prime[Range[200]], Mod[#, 4]==1&]] (* Harvey P. Dale, Feb 05 2020 *) PROG (PARI) p=5; forprime(q=7, 1e3, if(q%4==1, print1(q-p", "); p=q)) \\ Charles R Greathouse IV, May 13 2012 CROSSREFS Cf. A002144, A002145, A082074, A082075, A082076. Sequence in context: A194184 A194217 A239971 * A244209 A156279 A203072 Adjacent sequences: A082070 A082071 A082072 * A082074 A082075 A082076 KEYWORD nonn,easy AUTHOR Labos Elemer, Apr 07 2003 STATUS approved

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Last modified April 2 08:27 EDT 2023. Contains 361723 sequences. (Running on oeis4.)