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

 

Logo

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 56th year, we are closing in on 350,000 sequences, and we’ve crossed 9,700 citations (which often say “discovered thanks to the OEIS”).

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A200049 Positions of squares of odd primes among odd powerful numbers A062739. 1
2, 3, 5, 7, 9, 12, 14, 16, 20, 21, 27, 29, 30, 34, 37, 44, 45, 48, 52, 53, 58, 61, 65, 71, 75, 76, 78, 79, 84, 93, 97, 100, 101, 109, 111, 115, 119, 122, 128, 132, 133, 142, 144, 146, 147, 157, 165, 169, 170, 172, 178, 180, 188, 193, 198, 202, 203, 207, 211, 213, 221, 231, 233, 234, 238, 251, 254, 261, 263, 267, 271 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Zak Seidov, Table of n, a(n) for n = 1..1000

FORMULA

A062739(a(n)) = (A000040(n+1))^2.

PROG

(PARI) lista(nn) = select(x->(issquare(x) && isprime(sqrtint(x))), select(x->(ispowerful(x) && (x % 2)), vector(nn, k, k)), 1); \\ Michel Marcus, Jun 18 2017

CROSSREFS

Cf. A000040, A062739.

Sequence in context: A254440 A284914 A293262 * A279984 A184017 A024195

Adjacent sequences:  A200046 A200047 A200048 * A200050 A200051 A200052

KEYWORD

nonn

AUTHOR

Zak Seidov, Nov 13 2011

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 December 8 21:59 EST 2021. Contains 349596 sequences. (Running on oeis4.)