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!)
A244557 Numbers obtained by concatenating the squares of the digits of prime(n). 2
4, 9, 25, 49, 11, 19, 149, 181, 49, 481, 91, 949, 161, 169, 1649, 259, 2581, 361, 3649, 491, 499, 4981, 649, 6481, 8149, 101, 109, 1049, 1081, 119, 1449, 191, 1949, 1981, 11681, 1251, 12549, 1369, 13649, 1499, 14981, 1641, 1811, 1819, 18149, 18181, 411, 449 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Harvey P. Dale, Table of n, a(n) for n = 1..1000

FORMULA

a(n) = A048385(A000040(n)).

EXAMPLE

For n = 7, prime(7) = 17 and a(7) = 149, which is the concatenation of the squares of the digits of 17. For n = 31, prime(31) = 127 and a(31) = 1449; but this term also appears at index 200, in fact prime(200) = 1223 and a(200) = 1449.

MATHEMATICA

Table[FromDigits[Flatten[IntegerDigits/@(IntegerDigits[Prime[n]]^2)]], {n, 50}] (* Harvey P. Dale, Aug 18 2016 *)

PROG

(MAGMA) [StringToInteger(&cat[IntegerToString(h): h in Reverse([i^2: i in Intseq(p)])]): p in PrimesUpTo(250)];

CROSSREFS

Cf. A000040, A048385.

Sequence in context: A158142 A158143 A082200 * A063482 A277312 A069557

Adjacent sequences:  A244554 A244555 A244556 * A244558 A244559 A244560

KEYWORD

nonn,base

AUTHOR

Vincenzo Librandi, Jul 02 2014

EXTENSIONS

Edited by Bruno Berselli, Jul 02 2014

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 August 13 19:30 EDT 2020. Contains 336451 sequences. (Running on oeis4.)