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A323354 Odd n such that A015525(n) is not squarefree. 2
5, 15, 25, 35, 45, 51, 55, 65, 75, 85, 95, 105, 115, 125, 135, 145, 153, 155, 165, 175, 185, 195, 205, 215, 225, 235, 245, 255, 265, 275, 285, 295, 305, 315, 325, 335, 345, 355, 357, 365, 375, 385, 395, 405, 415, 425, 435, 445, 455, 459, 465, 475, 485 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
EXAMPLE
a(1) = 5: A015525(5) = 361 = 19^2. All multiples of 5 are in the sequence and have 19^2 as a factor.
a(6) = 51: A015525(51) = 3005793749329960987137864733842257 = 17^2 * 67 * 307 * 624669523 * 809464558443747299.
PROG
(PARI) anm2=1; anm1=3; for(n=3, 155, an=3*anm1+8*anm2; anm2=anm1; anm1=an; if(n%2&&!issquarefree(an), print1(n, ", ")))
CROSSREFS
Sequence in context: A043509 A121025 A277592 * A172404 A031322 A017329
KEYWORD
nonn
AUTHOR
Hugo Pfoertner, Jan 12 2019
STATUS
approved

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Last modified March 19 03:18 EDT 2024. Contains 370952 sequences. (Running on oeis4.)