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A054994 Numbers of the form (q1^b1)(q2^b2)(q3^b3)(q4^b4)(q5^b5)... where q1=5, q2=13, q3=17, q4=29, q5=37, ... [A002144] and b1>=b2>=b3>=b4>=b5... 9
1, 5, 25, 65, 125, 325, 625, 1105, 1625, 3125, 4225, 5525, 8125, 15625, 21125, 27625, 32045, 40625, 71825, 78125, 105625, 138125, 160225, 203125, 274625, 359125, 390625, 528125, 690625, 801125, 1015625, 1185665, 1221025, 1373125, 1795625 (list; graph; refs; listen; history; internal format)
OFFSET

1,2

COMMENTS

This sequence is related to Pythagorean triples regarding the number of hypotenuses which are in a particular number of total Pythagorean triples and a particular number of primitive Pythagorean triples.

Least integer "mod 4 prime signature" values that are the hypotenuse of at least one primitive Pythagorean triple - Ray Chandler (rayjchandler(AT)sbcglobal.net), Aug 26 2004

See A097751 for definition of "mod 4 prime signature"; terms of A097752 with all prime factors of form 4k+1.

LINKS

Ray Chandler, Table of n, a(n) for n = 1..10000

Eric Weisstein's World of Mathematics, Pythagorean Triple

EXAMPLE

1=5^0, 5=5^1, 25=5^2, 65=(5)(13), 125=5^3, 325=(5^2)(13), 625=5^4, etc.

CROSSREFS

Cf. A002144, A097751-A097756.

Sequence in context: A060820 A146404 A179131 * A108403 A007058 A071383

Adjacent sequences:  A054991 A054992 A054993 * A054995 A054996 A054997

KEYWORD

easy,nonn

AUTHOR

Bernard Altschuler (Altschuler_B(AT)bls.gov), May 30 2000

EXTENSIONS

More terms from Henry Bottomley (se16(AT)btinternet.com), Mar 14 2001

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Last modified February 15 09:00 EST 2012. Contains 205744 sequences.