The OEIS mourns the passing of Jim Simons and is grateful to the Simons Foundation for its support of research in many branches of science, including the OEIS.
The OEIS is supported by the many generous donors to the OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A340636 Primes of the form k + A037276(k) in more than one way. 3
 251, 2671, 2687, 2753, 23327, 23561, 27827, 28499, 28789, 28817, 29411, 34757, 223441, 226001, 227537, 230849, 231359, 232217, 232259, 232367, 232643, 232919, 233591, 234791, 236129, 236609, 236867, 237857, 238141, 239023, 239873, 240899, 241169, 241343, 241687, 241691, 242447, 242747, 245299 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Robert Israel, Table of n, a(n) for n = 1..7500 EXAMPLE a(3) = 2687 = 170 + A037276(170) = 170 + 2517 = 458 + A037276(458) = 458 + 2229. The first term that occurs in more than two ways is a(163) = 2255299 = 4180 + A037276(4180) = 4180 + 2251119 = 21156 + A037276(21156) = 21156 + 2234143 = 29560 + A037276(29560) = 29560 + 2225739. MAPLE N:= 5*10^5: # for terms <= N dcat:= proc(L) local i, x; x:= L[-1]; for i from nops(L)-1 to 1 by -1 do x:= 10^(1+ilog10(x))*L[i]+x od; x end proc: A037276:= proc(n) local F; F:= sort(ifactors(n)[2], (a, b) -> a[1] < b[1]); dcat(map(t -> t[1]\$t[2], F)); end proc: A037276(1):= 1: R:= NULL: for n from 1 to N/2 do v:= n + A037276(n); if v < N and isprime(v) then R:= R, v fi; od: S:= {R}: select(s -> numboccur(s, [R])>1, S); CROSSREFS Cf. A037276, A340633, A340634. Sequence in context: A033451 A201793 A183840 * A234929 A218639 A090834 Adjacent sequences: A340633 A340634 A340635 * A340637 A340638 A340639 KEYWORD nonn,base AUTHOR J. M. Bergot and Robert Israel, Jan 14 2021 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified May 26 16:43 EDT 2024. Contains 372840 sequences. (Running on oeis4.)