The On-Line Encyclopedia of Integer Sequences (OEIS)

Revision History for A174216 (Bold, blue-underlined text is an addition; faded, red-underlined text is a ~~deletion~~.)
Showing entries 1-10 | older changes

A174216

a(1)=15; for n>1, a(n) = the smallest number k >a(n-1) such that 2*A174214(k)= 3*(k-1).
(history; published version)

#14 by Susanna Cuyler at Mon Dec 10 08:53:15 EST 2018

STATUS

proposed

approved

#13 by Michel Marcus at Mon Dec 10 03:20:54 EST 2018

STATUS

editing

proposed

#12 by Michel Marcus at Mon Dec 10 03:20:50 EST 2018

KEYWORD

nonn,more

STATUS

approved

editing

#11 by Bruno Berselli at Tue Feb 02 02:55:01 EST 2016

STATUS

proposed

approved

#10 by Michel Marcus at Tue Feb 02 02:25:27 EST 2016

STATUS

editing

proposed

#9 by Michel Marcus at Tue Feb 02 02:24:17 EST 2016

LINKS

V. Shevelev, <a href="http://arXiv.org/abs/0912.4006">Theorems on twin primes-dual case</a>, arXiv:0912.4006 [math.GM], 2009-2014.

MAPLE

A174216 := proc(n) option remember ; if n =1 then 15 ; else for k from procname(n-1)+1 do if 2*A173214(k) = 3*(k-1) then return k; end if; end do ; end if; end proc: # _R. J. Mathar, _, Mar 16 2010

CROSSREFS

Cf. A174214, A174215, A166945, A167495.

EXTENSIONS

I corrected the terms beginning with a(11) and added some new terms. - Vladimir Shevelev, Mar 27 2010

STATUS

proposed

editing

#8 by Jean-François Alcover at Tue Feb 02 02:21:08 EST 2016

STATUS

editing

proposed

#7 by Jean-François Alcover at Tue Feb 02 02:20:56 EST 2016

MATHEMATICA

(* b = A174214 *) b[n_] := b[n] = Which[n==9, 14, CoprimeQ[b[n-1], n-1- (-1)^n], b[n-1]+1, True, 2n-4]; a[n_] := a[n] = If[n==1, 15, For[k = a[n- 1]+1, True, k++, If[2b[k] == 3(k-1), Return[k]]]]; Table[Print["a(", n, ") = ", a[n]]; a[n], {n, 1, 22}] (* Jean-François Alcover, Feb 02 2016 *)

STATUS

approved

editing

#6 by Russ Cox at Fri Mar 30 18:52:53 EDT 2012

AUTHOR

_Vladimir Shevelev (shevelev(AT)bgu.ac.il), _, Mar 12 2010

EXTENSIONS

I corrected the terms beginning with a(11) and added some new terms. - _Vladimir Shevelev (shevelev(AT)bgu.ac.il), _, Mar 27 2010

Terms from a(11) onwards were corrected according to independent calculations by R. Mathar, M. Alekseyev, M. Hasler and A. Heinz (SeqFan lists 30 Oct and 1 Nov 2010). - _Vladimir Shevelev (shevelev(AT)bgu.ac.il), _, Nov 02 2010

Discussion

Fri Mar 30

18:52

OEIS Server: https://oeis.org/edit/global/261

#5 by Russ Cox at Fri Mar 30 17:40:18 EDT 2012

EXTENSIONS

Terms from a(11) on corrected by _R. J. Mathar (mathar(AT)strw.leidenuniv.nl), _, Mar 16 2010

Discussion

Fri Mar 30

17:40

OEIS Server: https://oeis.org/edit/global/190