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A004094 Powers of 2 written backwards. 23
1, 2, 4, 8, 61, 23, 46, 821, 652, 215, 4201, 8402, 6904, 2918, 48361, 86723, 63556, 270131, 441262, 882425, 6758401, 2517902, 4034914, 8068838, 61277761, 23445533, 46880176, 827712431, 654534862, 219078635, 4281473701, 8463847412 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

Freeman Dyson believes that A014963(a(n))<>5 is true but cannot be proved, see link. - Reinhard Zumkeller, Jan 05 2005

a(n) = A004086(A000079(n)). - Reinhard Zumkeller, Apr 02 2014

LINKS

T. D. Noe, Table of n, a(n) for n = 0..1000

Richard Lipton, More on testing Dyson's conjecture (2014)

Edge Foundation, Annual Question 2005

PROG

(Haskell)

a004094 = a004086 . a000079  -- Reinhard Zumkeller, Apr 02 2014

(PARI) rev(n)=subst(Polrev(digits(n)), 'x, 10)

a(n)=rev(2^n) \\ Charles R Greathouse IV, Oct 20 2014

CROSSREFS

Cf. A102382, A102383, A102384, A102385.

The following are parallel families: A000079 (2^n), A004094 (2^n reversed), A028909 (2^n sorted up), A028910 (2^n sorted down), A036447 (double and reverse), A057615 (double and sort up), A263451 (double and sort down); A000244 (3^n), A004167 (3^n reversed), A321540 (3^n sorted up), A321539 (3^n sorted down), A163632 (triple and reverse), A321542 (triple and sort up), A321541 (triple and sort down).

Sequence in context: A206850 A094333 A018473 * A028910 A018482 A036447

Adjacent sequences:  A004091 A004092 A004093 * A004095 A004096 A004097

KEYWORD

nonn,base,easy

AUTHOR

N. J. A. Sloane.

EXTENSIONS

More terms from Reinhard Zumkeller, Jan 05 2005

STATUS

approved

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Last modified January 18 06:34 EST 2019. Contains 319269 sequences. (Running on oeis4.)