login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A102174 Iccanobirt semiprime indices (4 of 15): Indices of semiprime numbers in A102114. 1
5, 11, 18, 33, 35, 37, 43, 44, 56, 63, 93, 148, 175, 176, 204, 288, 317 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

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

FORMULA

A102114(a(n)) = A102194(n).

MATHEMATICA

nxt[{a_, b_, c_}]:={b, c, IntegerReverse[c]+b+a}; Flatten[Position[ NestList[ nxt, {0, 0, 1}, 200][[All, 1]], _?(PrimeOmega[#]==2&)]]-1 (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, May 16 2018 *)

CROSSREFS

Cf. A001358, A102114, A102171-A102185, A102194.

Sequence in context: A240438 A140697 A048253 * A140515 A056996 A102184

Adjacent sequences:  A102171 A102172 A102173 * A102175 A102176 A102177

KEYWORD

nonn,more,less,base

AUTHOR

Jonathan Vos Post and Ray Chandler, Dec 31 2004

EXTENSIONS

a(15) from Robert Price, Nov 08 2018

Offset changed to 1 and a(16)-a(17) from Jinyuan Wang, Aug 10 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 | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified September 20 17:42 EDT 2021. Contains 347588 sequences. (Running on oeis4.)