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A038243 Triangle whose (i,j)-th entry is binomial(i,j)*5^(i-j)*1^j. 5
1, 5, 1, 25, 10, 1, 125, 75, 15, 1, 625, 500, 150, 20, 1, 3125, 3125, 1250, 250, 25, 1, 15625, 18750, 9375, 2500, 375, 30, 1, 78125, 109375, 65625, 21875, 4375, 525, 35, 1, 390625, 625000, 437500, 175000, 43750, 7000, 700, 40, 1, 1953125 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

Mirror image of A013612. - Zerinvary Lajos, Nov 25 2007

T(i,j) is the number of i-permutations of 6 objects a,b,c,d,e,f, with repetition allowed, containing j a's. - Zerinvary Lajos, Dec 21 2007

Triangle of coefficients in expansion of (5+x)^n - N-E. Fahssi, Apr 13 2008

REFERENCES

B. N. Cyvin et al., Isomer enumeration of unbranched catacondensed polygonal systems with pentagons and heptagons, Match, No. 34 (Oct 1996), pp. 109-121.

LINKS

Table of n, a(n) for n=0..45.

FORMULA

See A038207 and A027465 and replace 2 and 3 in analogous formulas with 5. - Tom Copeland, Oct 26 2012

EXAMPLE

1

5, 1

25, 10, 1

125, 75, 15, 1

625, 500, 150, 20, 1

3125, 3125, 1250, 250, 25, 1

15625, 18750, 9375, 2500, 375, 30, 1

78125, 109375, 65625, 21875, 4375, 525, 35, 1

390625, 625000, 437500, 175000, 43750, 7000, 700, 40, 1

MAPLE

for i from 0 to 8 do seq(binomial(i, j)*5^(i-j), j = 0 .. i) od; # Zerinvary Lajos, Dec 21 2007

CROSSREFS

Cf. A000351, A053464, A081135, A081143, A036071, A050982.

Sequence in context: A123967 A162259 A077195 * A286231 A218016 A193685

Adjacent sequences:  A038240 A038241 A038242 * A038244 A038245 A038246

KEYWORD

nonn,tabl,easy

AUTHOR

N. J. A. Sloane.

STATUS

approved

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Last modified October 18 10:10 EDT 2018. Contains 316320 sequences. (Running on oeis4.)